UnicodeDecodeError charmap (On Windows)

[yarbs]

lineno 97-99 for https://github.com/dadadel/pyment/blob/master/pyment/pyment.py
encoding is not defined when opening the file, default encoding on windows is cp1252 and fails when a unicode character is encountered.

Suggest adding an argument to argparse and add a parameter to init of PyComment.

[J-K-M]

If using the -w flag then this issue also arrises on write - line 325.
This could likely be fixed in the same way.