Remove all .pyc files from a git repository

When working on Python project you may sometimes forget to .gitignore your
*.pyc files and end up having them tracked by the repo.

To fix this you need use git rm:

find . -name "*.pyc" -exec git rm -f {} \;

Then, add a line:

*.pyc

to the .gitignore file in the repository root to have them permanently
ignored.

Credit goes to Yuji.