added get/setAlias command to Attribute
added get/setAlias command to Attribute

shrtcww/pymel,shrtcww/pymel,juggernate/pymel,assumptionsoup/pymel,leonsooi/pymel,assumptionsoup/pymel,AtonLerin/pymel,juggernate/pymel,cgrebeld/pymel,leonsooi/pymel,AtonLerin/pymel,david-lassonde-adsk/pymel,david-lassonde-adsk/pymel