fix($cordovaDeviceMotion): proper handling when no accelerometer available
fix($cordovaDeviceMotion): proper handling when no accelerometer available

Add missing return statement to avoid plugin crash when there is no acceelerometer on the device

Closes issue #1190

SidneyS/ng-cordova,driftyco/ng-cordova,nraboy/ng-cordova,SidneyS/ng-cordova,driftyco/ng-cordova,nraboy/ng-cordova,nraboy/ng-cordova,ralic/ng-cordova,ralic/ng-cordova,driftyco/ng-cordova,ralic/ng-cordova,SidneyS/ng-cordova