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Note that this setting will "stick" until turned off manually, or until you re-clone the repository. So don't use it on files you have changed but don't want to commit yet, unless you are prepared to manually set the bit afterword.

Github easter egg: add ?w=0 to diff URLs (eg a commit, compare view or pull request) to ignore whitespace

Good article on pull request best practices:

http://codeinthehole.com/writing/pull-requests-and-other-good-practices-for-teams-using-github/

Get Git

Follow the instructions for your environment here:
http://git-scm.com/

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