Ignore not attached receptors in BasicDeliveryController.
TODO in PDUController. Have no time to fix it right now :S
Force PDU to read current power status values in RouterWithPDUPowerController getPowerStatus.

Don't trust GIM model when getPowerStatus is called in RouterWithPDUPowerController. As it may be out of date.
Instead, force the PDU to update GIM model with current power status, before reporting it in the router.
Merge pull request #625 from isartcanyameres/fix/gim-controllers

Fix/gim controllers