Always return HTML in git_not_found
Always return HTML in git_not_found

This allows us to give a nice 404 for e.g. archive.zip.

Datacom/gitlabhq,jirutka/gitlabhq,Telekom-PD/gitlabhq,ttasanen/gitlabhq,mrb/gitlabhq,jrjang/gitlabhq,t-zuehlsdorff/gitlabhq,duduribeiro/gitlabhq,sonalkr132/gitlabhq,szechyjs/gitlabhq,darkrasid/gitlabhq,Soullivaneuh/gitlabhq,daiyu/gitlab-zh,MauriceMohlek/gitlabhq,cui-liqiang/gitlab-ce,fpgentil/gitlabhq,allysonbarros/gitlabhq,cui-liqiang/gitlab-ce,mmkassem/gitlabhq,LUMC/gitlabhq,martijnvermaat/gitlabhq,dplarson/gitlabhq,stoplightio/gitlabhq,louahola/gitlabhq,szechyjs/gitlabhq,jirutka/gitlabhq,mmkassem/gitlabhq,mr-dxdy/gitlabhq,t-zuehlsdorff/gitlabhq,dwrensha/gitlabhq,jrjang/gitlab-ce,yatish27/gitlabhq,SVArago/gitlabhq,larryli/gitlabhq,koreamic/gitlabhq,daiyu/gitlab-zh,larryli/gitlabhq,MauriceMohlek/gitlabhq,ksoichiro/gitlabhq,Telekom-PD/gitlabhq,Telekom-PD/gitlabhq,mr-dxdy/gitlabhq,duduribeiro/gitlabhq,ferdinandrosario/gitlabhq,ttasanen/gitlabhq,jrjang/gitlab-ce,ikappas/gitlabhq,allysonbarros/gitlabhq,martijnvermaat/gitlabhq,louahola/gitlabhq,fpgentil/gitlabhq,Soullivaneuh/gitlabhq,duduribeiro/gitlabhq,LUMC/gitlabhq,mmkassem/gitlabhq,louahola/gitlabhq,SVArago/gitlabhq,jirutka/gitlabhq,iiet/iiet-git,dwrensha/gitlabhq,ksoichiro/gitlabhq,dplarson/gitlabhq,mrb/gitlabhq,axilleas/gitlabhq,openwide-java/gitlabhq,shinexiao/gitlabhq,Datacom/gitlabhq,sonalkr132/gitlabhq,icedwater/gitlabhq,allysonbarros/gitlabhq,jrjang/gitlabhq,iiet/iiet-git,MauriceMohlek/gitlabhq,duduribeiro/gitlabhq,mrb/gitlabhq,dreampet/gitlab,ferdinandrosario/gitlabhq,Datacom/gitlabhq,ttasanen/gitlabhq,darkrasid/gitlabhq,daiyu/gitlab-zh,ikappas/gitlabhq,screenpages/gitlabhq,yatish27/gitlabhq,ferdinandrosario/gitlabhq,shinexiao/gitlabhq,openwide-java/gitlabhq,screenpages/gitlabhq,koreamic/gitlabhq,martijnvermaat/gitlabhq,stoplightio/gitlabhq,koreamic/gitlabhq,ferdinandrosario/gitlabhq,shinexiao/gitlabhq,stoplightio/gitlabhq,sonalkr132/gitlabhq,dreampet/gitlab,larryli/gitlabhq,axilleas/gitlabhq,fpgentil/gitlabhq,Telekom-PD/gitlabhq,yatish27/gitlabhq,daiyu/gitlab-zh,SVArago/gitlabhq,htve/GitlabForChinese,ikappas/gitlabhq,iiet/iiet-git,jrjang/gitlabhq,dplarson/gitlabhq,SVArago/gitlabhq,Soullivaneuh/gitlabhq,mr-dxdy/gitlabhq,jrjang/gitlab-ce,dwrensha/gitlabhq,screenpages/gitlabhq,mr-dxdy/gitlabhq,jirutka/gitlabhq,openwide-java/gitlabhq,LUMC/gitlabhq,dwrensha/gitlabhq,jrjang/gitlabhq,darkrasid/gitlabhq,axilleas/gitlabhq,cui-liqiang/gitlab-ce,mrb/gitlabhq,jrjang/gitlab-ce,mmkassem/gitlabhq,louahola/gitlabhq,yatish27/gitlabhq,axilleas/gitlabhq,iiet/iiet-git,shinexiao/gitlabhq,htve/GitlabForChinese,larryli/gitlabhq,ksoichiro/gitlabhq,MauriceMohlek/gitlabhq,cui-liqiang/gitlab-ce,szechyjs/gitlabhq,ksoichiro/gitlabhq,sonalkr132/gitlabhq,ikappas/gitlabhq,LUMC/gitlabhq,fpgentil/gitlabhq,martijnvermaat/gitlabhq,dplarson/gitlabhq,stoplightio/gitlabhq,openwide-java/gitlabhq,dreampet/gitlab,icedwater/gitlabhq,htve/GitlabForChinese,darkrasid/gitlabhq,ttasanen/gitlabhq,Datacom/gitlabhq,koreamic/gitlabhq,icedwater/gitlabhq,htve/GitlabForChinese,dreampet/gitlab,allysonbarros/gitlabhq,screenpages/gitlabhq,Soullivaneuh/gitlabhq,t-zuehlsdorff/gitlabhq,t-zuehlsdorff/gitlabhq,szechyjs/gitlabhq,icedwater/gitlabhq