Add doc about backporting changes from EE to CE
Add doc about backporting changes from EE to CE

axilleas/gitlabhq,iiet/iiet-git,dreampet/gitlab,mmkassem/gitlabhq,iiet/iiet-git,stoplightio/gitlabhq,dreampet/gitlab,dreampet/gitlab,jirutka/gitlabhq,mmkassem/gitlabhq,axilleas/gitlabhq,jirutka/gitlabhq,mmkassem/gitlabhq,iiet/iiet-git,stoplightio/gitlabhq,stoplightio/gitlabhq,axilleas/gitlabhq,mmkassem/gitlabhq,jirutka/gitlabhq,stoplightio/gitlabhq,jirutka/gitlabhq,iiet/iiet-git,axilleas/gitlabhq,dreampet/gitlab