Don't rebuild diverging commit count caches
Don't rebuild diverging commit count caches

When calling Repository#build_cache we _don't_ want to build the
diverging commit count cache as doing so can be _very_ slow for
repositories with lots of branches. Because these caches are built
whenever needed (= when actually viewing the list of branches in the web
UI) we can safely remove this code from
Repository#build_cache.

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