Allow moveableoninput access to ctrl layer
Remove the private _moveable_on_input var to use the controller axis attribute. The previous behavior has been kept by a basic implementation of Get/SetAxis par in TriggerGateController.
The main idea is allow to some controller like IcepapTriggerController to genenerate this dictionary automatically, so no user interaction is needed.
It changes the original desing of this attribute (internal of sardana) discussed here: #1679 (closed)