Fix problems with '#' in branchname

Add proper escaping of '#' in branchname in compare when doing pull
requests. This addresses issue #2822.

templates/repo/pulls/compare.tmpl

@@ -21,7 +21,7 @@
 						</div>
 						<div class="scrolling menu">
 							{{range .Branches}}
-								<div class="item {{if eq $.BaseBranch .}}selected{{end}}" data-url="{{$.RepoLink}}/compare/{{.}}...{{if not $.PullRequestCtx.SameRepo}}{{$.HeadUser.Name}}:{{end}}{{$.HeadBranch}}">{{.}}</div>
+								<div class="item {{if eq $.BaseBranch .}}selected{{end}}" data-url="{{$.RepoLink}}/compare/{{EscapePound .}}...{{if not $.PullRequestCtx.SameRepo}}{{$.HeadUser.Name}}:{{end}}{{EscapePound $.HeadBranch}}">{{.}}</div>
 							{{end}}
 						</div>
 					</div>
@@ -39,7 +39,7 @@
 						</div>
 						<div class="scrolling menu">
 							{{range .HeadBranches}}
-								<div class="{{if eq $.HeadBranch .}}selected{{end}} item" data-url="{{$.RepoLink}}/compare/{{$.BaseBranch}}...{{if not $.PullRequestCtx.SameRepo}}{{$.HeadUser.Name}}:{{end}}{{.}}">{{.}}</div>
+								<div class="{{if eq $.HeadBranch .}}selected{{end}} item" data-url="{{$.RepoLink}}/compare/{{EscapePound $.BaseBranch}}...{{if not $.PullRequestCtx.SameRepo}}{{$.HeadUser.Name}}:{{end}}{{EscapePound .}}">{{.}}</div>
 							{{end}}
 						</div>
 					</div>