Git commit formatting and spell check

If you have a hard time remembering to format your git commits properly, you can add this simple line to your .vimrc file:

autocmd Filetype gitcommit setlocal spell textwidth=72

This will:
- Highlight formatting of your commit message (50 characters, no period)
- Spell check (you need to install aspell)
- Auto wordwrap your extended message at 72 characters