Implemented jQuery.wikibase.sitelinkgroupview

jQuery.wikibase.sitelinkgroupview acts as a container for a sitelinklistview widget specific
to a particular site link group.

Change-Id: Iad39d3c808f55cf093b7b2c79d8ae04f93ee5d12
Merge "Implemented jQuery.wikibase.sitelinkgroupview"