DOC: update contributing guide regarding updating a pull request (merge master)#19990

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jorisvandenbossche merged 4 commits intopandas-dev:masterfrom

jorisvandenbossche:doc-contributing-update

Mar 16, 2018

Commits on Mar 5, 2018

DOC: update contributing guide regarding updating a pull request (merge master)
jorisvandenbossche
committed

Commits on Mar 8, 2018

remove rebasing for updating branch + add pull for updating master
jorisvandenbossche
committed

Commits on Mar 15, 2018