Changed propel to prepared statements
CC-5172 : errors from setting cues in waveform editor not handled properly

Conflicts:
	airtime_mvc/application/models/Playlist.php
CC-5172 : errors from setting cues in waveform editor not handled properly

Conflicts:
	airtime_mvc/application/models/Playlist.php
make operators more local to each queue source

Conflicts:
	python_apps/pypo/liquidsoap_scripts/ls_script.liq
create on_metadata callback for each source instead of once on unified source

Conflicts:
	python_apps/pypo/liquidsoap_scripts/ls_script.liq