Handle line ending

This PR makes sure all invisible line ending are `\n`. Unix compatible and not `^M` Windows style.

More information can be found at:
https://help.github.com/articles/dealing-with-line-endings#platform-linux

See also:
http://stackoverflow.com/questions/1510798/trying-to-fix-line-endings-with-git-filter-branch-but-having-no-luck/1511273#1511273