move changelog to 8.13
move changelog to 8.13

jirutka/gitlabhq,dreampet/gitlab,stoplightio/gitlabhq,iiet/iiet-git,darkrasid/gitlabhq,t-zuehlsdorff/gitlabhq,darkrasid/gitlabhq,openwide-java/gitlabhq,htve/GitlabForChinese,daiyu/gitlab-zh,jirutka/gitlabhq,LUMC/gitlabhq,screenpages/gitlabhq,stoplightio/gitlabhq,t-zuehlsdorff/gitlabhq,shinexiao/gitlabhq,screenpages/gitlabhq,jirutka/gitlabhq,icedwater/gitlabhq,htve/GitlabForChinese,darkrasid/gitlabhq,allysonbarros/gitlabhq,darkrasid/gitlabhq,htve/GitlabForChinese,daiyu/gitlab-zh,shinexiao/gitlabhq,axilleas/gitlabhq,dplarson/gitlabhq,LUMC/gitlabhq,stoplightio/gitlabhq,t-zuehlsdorff/gitlabhq,axilleas/gitlabhq,t-zuehlsdorff/gitlabhq,icedwater/gitlabhq,LUMC/gitlabhq,daiyu/gitlab-zh,dplarson/gitlabhq,icedwater/gitlabhq,stoplightio/gitlabhq,shinexiao/gitlabhq,dreampet/gitlab,allysonbarros/gitlabhq,openwide-java/gitlabhq,htve/GitlabForChinese,icedwater/gitlabhq,dreampet/gitlab,dplarson/gitlabhq,allysonbarros/gitlabhq,dplarson/gitlabhq,allysonbarros/gitlabhq,iiet/iiet-git,iiet/iiet-git,openwide-java/gitlabhq,dreampet/gitlab,jirutka/gitlabhq,iiet/iiet-git,mmkassem/gitlabhq,openwide-java/gitlabhq,axilleas/gitlabhq,axilleas/gitlabhq,mmkassem/gitlabhq,screenpages/gitlabhq,screenpages/gitlabhq,mmkassem/gitlabhq,mmkassem/gitlabhq,daiyu/gitlab-zh,shinexiao/gitlabhq,LUMC/gitlabhq