Fix #395: change node name does not refresh in the inspector until you reselect it

- added missing _node_renamed function to SceneTreeDock
Merge pull request #717 from rollenrolm/fix-inspector-rename-update

Fix #395: change node name does not refresh in the inspector until you r...
-variables with export in script are now IMMEDIATELY AND ALWAYS visible in properties (#718)
-WorldEnvironment cleanup issues fixed (#563)
-Text Editor improvement to shift-mouse selection (#648)
-(Hopefully) fixed rare (but horrible) indexing bug in GDScript compiler (#652)
-Some changes to PhysicsBody API, renamed property "active" to "sleeping", which makes more sense
-Added add_collision_exception() API in PhysicsBody (more accessible)
-ability to select and copy in the output messages panel
-added collision exception to 3D Physics API too
Merge remote-tracking branch 'upstream/master' into new-default-theme