- Removed old convention that only allowed one "IK" connection for Bones in a joint. Was highly frustrating for editing trees or branches. In a next commit, there will be a different method to define IK target and IK root, so this option actually will become "Connect Bone" or so. - the IK group name is gone, now is just an option "Tree IK". When IK chains share a root they'll form a tree. Todo is preventing conflicts here (will be for editor to define IK Root) - Adding new IK constraint with CTRL+I activates Constraint