language-detection

- add some better emojis to the README
- move the test imports inside the test functions: because the students will have to write functions that do not exist at the start of the class, the error message are pretty obscur
```
pytest
============================= test session starts ==============================
platform linux -- Python 3.10.12, pytest-8.2.2, pluggy-1.5.0
rootdir: /home/disc/a.stevan/documents/repos/gitlab.isae-supaero.fr/mae/language-detection
collected 0 items / 5 errors

==================================== ERRORS ====================================
_________ ERROR collecting tests/test_compute_occurence_frequencies.py _________
ImportError while importing test module '/home/disc/a.stevan/documents/repos/gitlab.isae-supaero.fr/mae/language-detection/tests/test_compute_occurence_frequencies.py'.
Hint: make sure your test modules/packages have valid Python names.
Traceback:
/usr/lib/python3.10/importlib/__init__.py:126: in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
tests/test_compute_occurence_frequencies.py:1: in <module>
    from src.enhanced_occurrence_frequencies import compute_occurence_frequencies
E   ModuleNotFoundError: No module named 'src.enhanced_occurrence_frequencies'
________________ ERROR collecting tests/test_detect_language.py ________________
ImportError while importing test module '/home/disc/a.stevan/documents/repos/gitlab.isae-supaero.fr/mae/language-detection/tests/test_detect_language.py'.
Hint: make sure your test modules/packages have valid Python names.
Traceback:
/usr/lib/python3.10/importlib/__init__.py:126: in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
tests/test_detect_language.py:1: in <module>
    from src.enhanced_occurrence_frequencies import (
E   ModuleNotFoundError: No module named 'src.enhanced_occurrence_frequencies'
____________________ ERROR collecting tests/test_entropy.py ____________________
ImportError while importing test module '/home/disc/a.stevan/documents/repos/gitlab.isae-supaero.fr/mae/language-detection/tests/test_entropy.py'.
Hint: make sure your test modules/packages have valid Python names.
Traceback:
/usr/lib/python3.10/importlib/__init__.py:126: in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
tests/test_entropy.py:1: in <module>
    from src.data_compression import entropy
E   ModuleNotFoundError: No module named 'src.data_compression'
____________________ ERROR collecting tests/test_kl_div.py _____________________
ImportError while importing test module '/home/disc/a.stevan/documents/repos/gitlab.isae-supaero.fr/mae/language-detection/tests/test_kl_div.py'.
Hint: make sure your test modules/packages have valid Python names.
Traceback:
/usr/lib/python3.10/importlib/__init__.py:126: in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
tests/test_kl_div.py:1: in <module>
    from src.enhanced_occurrence_frequencies import (
E   ModuleNotFoundError: No module named 'src.enhanced_occurrence_frequencies'
___________________ ERROR collecting tests/test_read_text.py ___________________
ImportError while importing test module '/home/disc/a.stevan/documents/repos/gitlab.isae-supaero.fr/mae/language-detection/tests/test_read_text.py'.
Hint: make sure your test modules/packages have valid Python names.
Traceback:
/usr/lib/python3.10/importlib/__init__.py:126: in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
tests/test_read_text.py:1: in <module>
    from src.enhanced_occurrence_frequencies import read_text
E   ModuleNotFoundError: No module named 'src.enhanced_occurrence_frequencies'
=========================== short test summary info ============================
ERROR tests/test_compute_occurence_frequencies.py
ERROR tests/test_detect_language.py
ERROR tests/test_entropy.py
ERROR tests/test_kl_div.py
ERROR tests/test_read_text.py
!!!!!!!!!!!!!!!!!!! Interrupted: 5 errors during collection !!!!!!!!!!!!!!!!!!!!
============================== 5 errors in 0.04s ===============================
```
now the errors will show
```
pytest
============================= test session starts ==============================
platform linux -- Python 3.10.12, pytest-8.2.2, pluggy-1.5.0
rootdir: /home/disc/a.stevan/documents/repos/gitlab.isae-supaero.fr/mae/language-detection
collected 6 items

tests/test_compute_occurence_frequencies.py FF                           [ 33%]
tests/test_detect_language.py F                                          [ 50%]
tests/test_entropy.py F                                                  [ 66%]
tests/test_kl_div.py F                                                   [ 83%]
tests/test_read_text.py F                                                [100%]

=================================== FAILURES ===================================
__________________________________ test_type ___________________________________

    def test_type():
>       from src.enhanced_occurrence_frequencies import compute_occurence_frequencies
E       ModuleNotFoundError: No module named 'src.enhanced_occurrence_frequencies'

tests/test_compute_occurence_frequencies.py:5: ModuleNotFoundError
_________________________________ test_output __________________________________

    def test_output():
>       from src.enhanced_occurrence_frequencies import compute_occurence_frequencies
E       ModuleNotFoundError: No module named 'src.enhanced_occurrence_frequencies'

tests/test_compute_occurence_frequencies.py:16: ModuleNotFoundError
_____________________________ test_detect_language _____________________________

    def test_detect_language():
>       from src.enhanced_occurrence_frequencies import (
            compute_occurence_frequencies, read_text, detect_language
        )
E       ModuleNotFoundError: No module named 'src.enhanced_occurrence_frequencies'

tests/test_detect_language.py:5: ModuleNotFoundError
_____________________________________ test _____________________________________

    def test():
>       from src.data_compression import entropy
E       ModuleNotFoundError: No module named 'src.data_compression'

tests/test_entropy.py:12: ModuleNotFoundError
_________________________________ test_kl_div __________________________________

    def test_kl_div():
>       from src.enhanced_occurrence_frequencies import (
            read_text, compute_occurence_frequencies, kl_divergence
        )
E       ModuleNotFoundError: No module named 'src.enhanced_occurrence_frequencies'

tests/test_kl_div.py:5: ModuleNotFoundError
________________________________ test_read_text ________________________________

    def test_read_text():
>       from src.enhanced_occurrence_frequencies import read_text
E       ModuleNotFoundError: No module named 'src.enhanced_occurrence_frequencies'

tests/test_read_text.py:2: ModuleNotFoundError
=========================== short test summary info ============================
FAILED tests/test_compute_occurence_frequencies.py::test_type - ModuleNotFoun...
FAILED tests/test_compute_occurence_frequencies.py::test_output - ModuleNotFo...
FAILED tests/test_detect_language.py::test_detect_language - ModuleNotFoundEr...
FAILED tests/test_entropy.py::test - ModuleNotFoundError: No module named 'sr...
FAILED tests/test_kl_div.py::test_kl_div - ModuleNotFoundError: No module nam...
FAILED tests/test_read_text.py::test_read_text - ModuleNotFoundError: No modu...
============================== 6 failed in 0.02s ===============================
```