CC-5227 - Sometimes Liquidsoap telnet is unresponsive which causes all Pypo threads to block

-initial commit
CC-5227 - Sometimes Liquidsoap telnet is unresponsive which causes all Pypo threads to block

-restart Liquidsoap if communication fails..
CC-5226:
Metadata isn't correct during playing

-should be fixed
CC-5226: Metadata isn't correct during playing

-fix incorrect metadata formatting
CC-5225 : Library: Fail to open Metadata Editor
CC-5226: Metadata isn't correct during playing

-fixed using "insert_metadata" and callbacks instead.
Merge branch '2.4.x' of dev.sourcefabric.org:airtime into 2.4.x
use he-aac v2 for fdk-aac
CC-5229: map_metadata in Liquidsoap is applied twice

fixed
CC-5230 : cc_pref can have duplicate keystrs when subjid is null
Merge branch '2.4.x' of dev.sourcefabric.org:airtime into 2.4.x
remove useless code and imports
Merge branch '2.4.x' of dev.sourcefabric.org:airtime into 2.4.x
Update airtime.po

finished :)
CC-5232 - During playback, a reinstall may push some tracks twice
Merge branch '2.4.x' of dev.sourcefabric.org:airtime into 2.4.x
Merge branch '2.4.x' of https://github.com/danielhjames/Airtime into 2.4.x
CC-5232: During playback, a reinstall may push some tracks twice
Merge branch '2.4.x' of dev.sourcefabric.org:airtime into 2.4.x
Liquidsoap restart shouldn't timeout