Add tests for remove_punctuation excluding apostrophes and fix a bug

[LKirst]

No description provided.

[alxwrd]

@LKirst looks good! Good catch with the bug.

Some flake8 errors from the build:

$ pipenv run flake8 . --exclude=build/
./test.py:12:74: W291 trailing whitespace
./test.py:14:80: E501 line too long (89 > 79 characters)
./test.py:19:71: W291 trailing whitespace
./test.py:21:80: E501 line too long (84 > 79 characters)
./test.py:26:71: W291 trailing whitespace
./test.py:28:80: E501 line too long (81 > 79 characters)
./test.py:224:1: E302 expected 2 blank lines, found 1
./test.py:231:1: E302 expected 2 blank lines, found 1
./textstat/textstat.py:168:9: E303 too many blank lines (2)

Codespell is also picking up:

$ pipenv run codespell -L paket --skip=./textstat/resources/**/easy_words.txt,./build/*,./textstat.egg-info/*
./test.py:28: youre ==> your, you're

Obviously this isn't a spelling mistake. Not sure what to do about this, as -L paket,youre might not be ideal.

[LKirst]

Codespell is also picking up:

$ pipenv run codespell -L paket --skip=./textstat/resources/**/easy_words.txt,./build/*,./textstat.egg-info/*
./test.py:28: youre ==> your, you're

Obviously this isn't a spelling mistake. Not sure what to do about this, as -L paket,youre might not be ideal.

@alxwrd, could we move the test string to a separate file and ignore that file instead of ignoring youre?

[alxwrd]

@LKirst thank you. I've reverted the __rm_apostrophe change, I got my logic inverted.