Update VE core submodule to master (8c7b4e2)

New changes:
f5d1e2a Create mixin that tries to execute primary node command
8c7b4e2 Actually add ClickableNode places

Change-Id: I7b641c620fbf28a4e98865c7d4e152d554017e70
Mixin ClickableNode and add primary command names

Created ve.ui.MWCommandRegistery, added inspector and dialog commands

Change-Id: I6b45018bdb719e36a85a785d4e08d32ee4b9b0a3