update to model-key getChanges
Merge pull request #994 from kandizzy/master

Update to model-key getChanges to prevent prev is undefined
settingZoomFromScope typo
Merge branch 'master' into develop

Conflicts:
	dist/angular-google-maps.js
	dist/angular-google-maps.min.js
	dist/angular-google-maps_dev_mapped.js
	dist/angular-google-maps_dev_mapped.js.map
	dist/angular-google-maps_dev_mapped.min.js
	dist/angular-google-maps_dev_mapped.min.js.map
post merge build