Remove .rails_footnotes from generated files since it is not used anymore
Allow to change the notes config directly from Footnotes.setup
Allow to configure more settings from Footnotes.setup
Rework README in preparation of release 4.0 [ci skip]
Remove backtrace monkeypatch that does not seem useful anymore and was only messing up with the backtrace in the logs
Add 4.0.0 to CHANGELOG
Emphasize we only support rails starting from 3.2
Bump version to 4.0.0 :beer: