Add ability to ignore file patterns

Flycheck for python generates temp files for each change done in the file even if the file has not been saved. So my_file.py will generate flycheck_my_file.py. As far as I can tell there is no way to change the path or extension of these files.

This creates a problem with pytest-watch. Whenever I change anything it runs the tests even if I havent saved the file. I would really like it to only run on file save. What would be nice was if --ignore could also ignore files by pattern similar to how .gitignore works. So I could run ptw --ignore flycheck* and not trigger a test when the flycheck files are generated.

Regardless, I am loving this tool. Thanks for developing it.

[freckletonj]

Emacs lock files endlessly trigger test runs. Autosaves are less frequent but still thorny. It would be nice if pytest-watch could respect .gitignore or custom regex/globs, eg: \#*\# and .\#*.

[KMontag42]

bump