new repo ui

- copy link button: #1396, #1168, #1668,
- synxtax highlight: #1712, #1549, #1315, #670
- z-index: #1942

conf/locale/locale_en-US.ini

@@ -387,7 +387,7 @@ repo_is_empty = This repository is empty, please come back later!
 
 branch = Branch
 tree = Tree
-branch_and_tags = Branches & Tags
+filter_branch_and_tag = Filter branch or tag
 branches = Branches
 tags = Tags
 issues = Issues