Added doc strings and comments throughout core/files.

[Dlux804]

Closes #9 issue.

[pep8speaks]

Hello @Dlux804! Thanks for updating this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file core/features.py:

Line 100:80: E128 continuation line under-indented for visual indent Line 100:80: E501 line too long (139 > 79 characters)

• In the file core/grid.py:

Line 22:80: E501 line too long (81 > 79 characters) Line 55:80: E501 line too long (81 > 79 characters) Line 57:80: E501 line too long (87 > 79 characters) Line 61:80: E501 line too long (83 > 79 characters) Line 85:80: E501 line too long (81 > 79 characters) Line 92:80: E501 line too long (156 > 79 characters) Line 124:80: E501 line too long (81 > 79 characters) Line 168:80: E501 line too long (81 > 79 characters) Line 183:32: E231 missing whitespace after ',' Line 241:80: E501 line too long (106 > 79 characters)

• In the file core/models.py:

Line 2:80: E501 line too long (83 > 79 characters) Line 17:80: E501 line too long (86 > 79 characters) Line 24:80: E501 line too long (93 > 79 characters)

• In the file core/regressors.py:

Line 42:80: E501 line too long (89 > 79 characters) Line 43:80: E501 line too long (102 > 79 characters)

• In the file main.py:

Line 21:49: E231 missing whitespace after ',' Line 21:80: E501 line too long (85 > 79 characters) Line 24:30: E231 missing whitespace after ',' Line 24:37: E231 missing whitespace after ',' Line 24:44: E231 missing whitespace after ',' Line 24:51: E231 missing whitespace after ',' Line 24:58: E231 missing whitespace after ',' Line 24:80: E501 line too long (86 > 79 characters) Line 70:1: W293 blank line contains whitespace

Comment last updated at 2020-01-24 20:00:11 UTC

[Dlux804]

Skipping review process. Functionality not changed, just cleaned up code and added docs and comments.