use common code for migrations

we have paged method defined in migration.py. update all scripts
to use this common code

Change-Id: Ia1a088f5ca9b2ab2f2b76aedb6853c7ff46b81a9
Remove unnecessary code from alarm test

test_put_alarm_wrong_field updates a local variable which is not used
any more, and it expects errors for request which will be responsed with
200.

Change-Id: I5d1fd224f47af74ea7a7409f88439cc65baf7c54
Merge "Remove unnecessary code from alarm test"
Merge "use common code for migrations"