Node, library, refactoring v1.6: squashed

Implement leaf-descriptor for restmpd

+remove duplicates in lists
+add "title" file info on tracks

Use mipod (rest mpd nodejs module) for most of MPD controls

+some refactor to organize JS in more files

Continue on switching from php to node

+clean code

Continue on moving to nodejs

- config nginx for nodejs proxy
- remove now useless forward.php
- refactor db browsing, remove old methods

Library toolbar

Force reload, status text, remove old loader, add spinner class, etc.

Library search

Search raw text

Fixed bug on clearing search lib

Node server.js

+ start to implement favorites filters feature

Manage lib favorites

Load and save favorites

Lib favorites: delete a file

Load library immediately from server

Library improve search text

Search ALL terms or search ANY term

[WIP] songs rating

Write lib tags (WIP)

Import mipod as a node package

+remove node_modules from git
+some instructions in node/README.md

Create package.json to allow easy install with dependencies

Receive playlist from mipod as explicit playlist item

Move MPD search to nodejs

and remove now unused monolithic parsing method

Use socket.io instead of REST for MPD

Use websocket for loading lib

Manage tags (rating)

Library - advanced search, rating

Minor fixes

- remove unnecessary notifies
- listen to deltag response
- add filters.advanced to search input when loading smart list

[WIP] reintegrate SPOP

Get spotify back, + manage idle loop

Update mipod dependency