fuzzy: add support for values associated with keys.
snippets: add template icon for snippet completion.
completion: load GdkPixbuf manually for now.
search: start on basic search provider interface
search: wire up providers to search completion.
search: start on global search using workspace panes as targets.
search: more plumbing of tab switching via global search.
search: show all matches, which should already be filtered.
search: pane is not necessarily a file.
search: do fuzzy matching for pane titles.