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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.
Ignore whitespace when viewing pull requests on github
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/
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