CORE-4720 Added app_groups/get-groups-for-app

Retrieves a listing of all groups the app with the given ID is listed under.
CORE-4720 Fix for app_groups/get-groups-for-app.

Updated get-groups-for-app to only return public groups.
CORE-4851 Fixed destructuring error.

The decategorize-app function is only called from one place in the metadactyl-clj project, and it's passing just the app-id as a string.
Updated this decategorize-app function to simply accept the app-id string.
CORE-4817 Added app-groups/get-suggested-groups-for-app.
CORE-4838: changed the version number and bumped the compatible database version number
Merge branch '1.8.4' of github.com:iPlantCollaborativeOpenSource/kameleon into 1.8.4