Clean up gcm code
Clean up gcm code

nickw444/airnotifier,batulu12/airnotifier,pathikb/airnotifier,University-of-Strathclyde-LTE-Team/airnotifier,imolainformatica/airnotifier,imolainformatica/airnotifier,nickw444/airnotifier,imolainformatica/airnotifier,University-of-Strathclyde-LTE-Team/airnotifier,pathikb/airnotifier,batulu12/airnotifier