Adds support for preview when editing an issue note (#5520).
Save queries.
Save 2 queries when displaying a root issue.
Save 1 query + 1 cache hit in #shared_versions for root projects.
Escapes wiki help link.
Prettier wiki syntax help link.
Adds wiki toolbar to notes editing form (#7899).
Load scripts and css for wiki formatter toolbar when needed.
Moves jstoolbar script include tags to head.
Context menu: keep parent item highlighted when hovering a submenu item.
