Wiki mirroring implementation (#3233)

* Implement wiki mirroring, add Update mirrors operation to admin dashboard

* bindata.go update after merge

* Implement checking Git repo endpoint existence, support for BB included

* Remove admin dashboard operation
Fix bindata.go

* Apply gofmt to repo model file

* Try to remove bindata from PR

* Revert accepted wiki names change in favor of better system

* Remove unused imports

modules/context/repo.go

@@ -223,6 +223,7 @@ func RepoAssignment(args ...bool) macaron.Handler {
 		ctx.Data["IsRepositoryOwner"] = ctx.Repo.IsOwner()
 		ctx.Data["IsRepositoryAdmin"] = ctx.Repo.IsAdmin()
 		ctx.Data["IsRepositoryWriter"] = ctx.Repo.IsWriter()
+		ctx.Data["IsRepositoryMirror"] = repo.IsMirror
 
 		ctx.Data["DisableSSH"] = setting.SSH.Disabled
 		ctx.Data["CloneLink"] = repo.CloneLink()