Formatting of git commit message

The Git commit textarea allows free form input. This is not helpful when writing git commit messages that can be easily read by other tools and on other platforms. For example, see Linus Torvalds' objection of using Github textarea for git commit messages

http://programmers.stackexchange.com/questions/149199/why-do-some-open-source-projects-do-not-accept-pull-requests-but-emailing-patch

Proposal
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Git commit text area can be customised to:

1. Limit line length to 72/80
2. Show hint of line length
3. Hard wrapping of lines