Changes

asterisk: Use (and fix) ActionID field in Action Login

The AMI documentation webpage mentions "ActionId", but Asterisk is
always returning "ActionID" in all response messages, so I'm using
that one to have proper patching when receiving the reponse.
In theory the keys are case insensitive, but I didn't find an easy
way to state that in TTCN-3 so far.

Change-Id: I9080f617c4e7272b9dd67d616069ac9350411f3c