residual vish work
Merge branch 'master' of github.com:ging/social_stream
Merge branch 'master' of github.com:ging/social_stream
2.1.0
Update license year
Remove references to @group in GroupsController

So inherit from the controller is possible
Generic Group.new_ js
Remove Relation::Custom strength methods
Use Relation::Owner for group creators
Include Relation::Owner in positive relations
Fix relation_list for groups
Fix doc

[ci skip]
Contact simple button
Remove followers_controller spec
Remove references to SocialStream.relation_model

The relation model is now inferred from
SocialStream.system_relations and SocialStream.custom_relations
Create Actors API and use it for group owners
SocialStream.available_permissions now working with STI and symbols
Allow reading Relation::Owner
Remove trace
Fix Relation::Single#available_permissions