FS-5358 --resolve use allow-transcoding=true param in global settings or fifo_allow_transcoding=true channel var on per caller basis

Conflicts:
	src/mod/applications/mod_fifo/mod_fifo.c
fix stopping of streams
add execute_on_pickup and api_on_pickup
add uuid of orig picked channel too
fix stop the correct way
add channel data to this event
FS-5359 --resolve
Merge remote branch 'stable/v1.2.stable' into v1.2.stable