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Add some git and github steps at contribution guidelines docs. Assuming most user in github has not experience with submit pull request. And this docs make things easy for new developer.
Closes#533 from ulysses-you/improve-contribution-guidelines.
Closes#533
ce116d2 [ulysses-you] nit
d70b322 [ulysses-you] fix
70fb548 [ulysses-you] docs
Authored-by: ulysses-you <ulyssesyou18@gmail.com>
Signed-off-by: ulysses-you <ulyssesyou18@gmail.com>
d397eb2cf1