Platform Team/Activity Library/4

Updates
To get update information for activity:

http://activities.sugarlabs.org/services/update-aslo.php?id=bundle_id[&appVersion=sugar-version][&experimental=1]

To get update information for collection:

http://activities.sugarlabs.org/services/micro-format.php?collection_nickname=collection-nick[&sugar=sugar-version]


 * if activity version was not set in collection and sugar request argument wasn't passed, then return recent activity version
 * if activity version was not set in collection and sugar request argument was passed, then return either recent activity version only for this sugar or nothing
 * if activity version was set in collection, regardless sugar request argument, exactly this version will be returned