Fixed loading MPD playlist with no extension

Files shown in root folder in web-ui without any file extension are now seen as playlists
Retrieve previous colour scheme (personal preference)
Removed unwanted scrolling

(can't figure out why it was there... may have side effects)
Playlist management: save playlists
Auto-set playlist name on loading playlist
Remove unimplemented stuff (browse mode)

Will have to implement it another way
Merge "back" line into above line

To gain some space in UI...
Revert "Updated player_lib.js for play\pause"

This reverts commit d1048cdac2da6514586e1aec677de838cb58ff1a.
Play/pause: make it explicit

Make it more explicit about what is the current state and what the click action is
New panel: library

Aiming to display library by Genre/artist/album
Load and display library (WIP)
[WIP] manage library filters

Also change "browse" icon
Lib filtering artist/album/genre

Allow browsing by genre/artist/album
[WIP] library: sort lists, play/enqueue buttons
Fix overlapping divs

With z-index rather than margin, to avoid horizontal scrollbar appears
Library: play, enqueue, play all, enqueue all

Had to hack around when sending MPD commands, due to MPD server apparently not understanding many commands closely sent
Revert "Retrieve previous colour scheme (personal preference)"

And use original CSS colors for library

This reverts commit 5d303beda37f82bf03861a0973c70c9ba959d6e9.
Better li CSS on library

Handle hover, special case for file list
Fixed chained MPD commands

(had to read response.. no sleep needed!)
PR comments: Clean code