Find in/Remove from/Send To/Go to playlist commands and too many playlists usability

[regorxxx]

Having to many playlists loaded at the same time may make those menu entries a bit cluttered, and hard to search what you are looking for.

This is the list of points I'm considering:

• Adding a playlist filter- configurable- to pre-filter those lists (for send selection/playlist to or Go to Playlist). That would greatly reduce the number of results. Rationale: Usually sending tracks or going to a playlist is related to a small set of playlists, and others are left untouched (for tagging purpose, classification, etc).
• 'Go To favorite playlist' button and/or menu, which only lists a pre-defined set of playlists. If you have 60 playlists but you usuallly need to move between 4 or 5 playlists frequently, those could be pinned to the menu for easy access. (have done something similar with Macro buttons, Pools button and configurable Search by Distance Button)
• Having a large number of playlists makes the menu slower to load (on click) since Find in.../Remove from... entries need to check all the playlists (and tracks within them). Another pre-filter for those menus would greatly speed up menu creation for extreme setups with hundreds of playlists. ( I would recommend the use of Playlist Manager SMP for those cases though).
• Around those lines, currently playlists within Playlist Manager are not considered at all for these menus. Maybe I could expand integration and allow to find/remove tracks in playlists files tracked by the manager too. That would allow to have most playlist un-loaded while still allowing to work with them.

If you have any suggestion around that, feel free to write them for next releases.