Allow to override PLY's debug/write_tables flags

[bfontaine]

This adds a way to remove the warnings in #65.

This is a draft PR because this works appear to work when I try it but I don’t know why my tests don’t pass. It’s midnight here so I’ll look into it tomorrow.

This PR adds two keyword arguments to the parse and parse_all functions:

• debug (default: False): this allows to control PLY’s parser.out debug file. Instead of relying on __debug__, which is virtually always true, we now default on not writing this file unless one passes debug=True.
• write_ply_tables (default: True): this is passed to PLY’s yacc.yacc as write_tables (see the docs). It’s True by default because it’s PLY’s default behavior, but one can disable this to prevent PLY from trying to write a parsetab.py cache file. It’s less efficient to do so, but it may help some people like on #65.

[bfontaine]

I mistakenly clicked on “New PR” instead of “New Draft PR” 🤦‍♂

[PlumpMath]

Thanks bfontaine

[bfontaine]

I ended up removing the tests: since this is just passing options down to PLY, testing this would mean testing PLY’s internals.

PLY It doesn’t close its debug file (https://github.com/dabeaz/ply/issues/200) so we have no way to guarantee that os.path.isfile("…path to the debug file…") is True at any point before the end of the program.