Search filtering, sorting

[kiith-sa]

Hovering over a search icon (add it) should allow to select what to search for (functions, classes, aliases, vars, templates, etc.)

Also, sorting of the search results could be improved (the last part of the fully qualified name should be the most important? So if I search for EntityManager that's what I get, not a million of other EntityManager related things. Also, shorter strings ("EntityManager") should be sorted before longer ("EntityMangerDiagnostics"))

The sorting could be affected by the number of references to each symbol. E.g. EntityManager is referenced often so it will be near the top.