See asterisk doco
featurepark
	parkext
	parkpos
	context
	parkingtime
	courtesytone
	parkedplay
	adsipark
	findslot
	parkedmusicclass
	transferdigittimeout
	xfersound
	xferfailsound
	pickupexten
	featuredigittimeout
	atxfernoanswertimeout

featuremap
	blindxfer
	disconnect
	automon
	atxfer
	parkcall