Update Git source installation steps to 2.7.3
Update Git source installation steps to 2.7.3

LUMC/gitlabhq,icedwater/gitlabhq,shinexiao/gitlabhq,daiyu/gitlab-zh,dreampet/gitlab,icedwater/gitlabhq,icedwater/gitlabhq,iiet/iiet-git,mr-dxdy/gitlabhq,shinexiao/gitlabhq,screenpages/gitlabhq,dplarson/gitlabhq,dreampet/gitlab,mmkassem/gitlabhq,axilleas/gitlabhq,stoplightio/gitlabhq,shinexiao/gitlabhq,dplarson/gitlabhq,larryli/gitlabhq,stoplightio/gitlabhq,LUMC/gitlabhq,htve/GitlabForChinese,allysonbarros/gitlabhq,stoplightio/gitlabhq,screenpages/gitlabhq,daiyu/gitlab-zh,darkrasid/gitlabhq,martijnvermaat/gitlabhq,t-zuehlsdorff/gitlabhq,mmkassem/gitlabhq,allysonbarros/gitlabhq,mmkassem/gitlabhq,dwrensha/gitlabhq,SVArago/gitlabhq,martijnvermaat/gitlabhq,openwide-java/gitlabhq,SVArago/gitlabhq,screenpages/gitlabhq,openwide-java/gitlabhq,Soullivaneuh/gitlabhq,dwrensha/gitlabhq,dreampet/gitlab,openwide-java/gitlabhq,SVArago/gitlabhq,mr-dxdy/gitlabhq,iiet/iiet-git,htve/GitlabForChinese,allysonbarros/gitlabhq,SVArago/gitlabhq,darkrasid/gitlabhq,openwide-java/gitlabhq,daiyu/gitlab-zh,jirutka/gitlabhq,axilleas/gitlabhq,dwrensha/gitlabhq,htve/GitlabForChinese,larryli/gitlabhq,Soullivaneuh/gitlabhq,dplarson/gitlabhq,axilleas/gitlabhq,iiet/iiet-git,jirutka/gitlabhq,t-zuehlsdorff/gitlabhq,mr-dxdy/gitlabhq,mmkassem/gitlabhq,Soullivaneuh/gitlabhq,allysonbarros/gitlabhq,shinexiao/gitlabhq,LUMC/gitlabhq,icedwater/gitlabhq,larryli/gitlabhq,daiyu/gitlab-zh,t-zuehlsdorff/gitlabhq,martijnvermaat/gitlabhq,darkrasid/gitlabhq,jirutka/gitlabhq,dplarson/gitlabhq,jirutka/gitlabhq,t-zuehlsdorff/gitlabhq,axilleas/gitlabhq,LUMC/gitlabhq,martijnvermaat/gitlabhq,darkrasid/gitlabhq,larryli/gitlabhq,htve/GitlabForChinese,iiet/iiet-git,dreampet/gitlab,mr-dxdy/gitlabhq,screenpages/gitlabhq,stoplightio/gitlabhq,dwrensha/gitlabhq,Soullivaneuh/gitlabhq