discard=on breaks for EFI disks

[wdoekes]

See #31 (comment)

[The] volume type would need to be available in the translator so it can skip setting discard=on if it sees type efidisk.

proxmove/proxmove

Lines 1860 to 1876 in 18fcd8d

	class AddDiscardOnTranslator(object):
	def volume_properties(self, new_volume):
	"""
	Add "discard=on" flag to properties if possible
	"""
	props = super().volume_properties(new_volume)
	if new_volume.storage and new_volume.storage.has_discard_support:
	values = props.split(',')
	name, rest = values[0], values[1:]
	rest = [
	i for i in rest if i not in ('discard=on', 'discard=off')]
	rest.append('discard=on')
	rest.sort()
	props = ','.join([name] + rest)
	return props

[wdoekes]

This PR addesses things: #46