Update VE core submodule to master (aad2986)

New changes:
66c6516 Filter out comments from external paste
4bde889 build: Fix script paths to be /bin/.. not /bin/../.. which isn't a thing
0bcfdbf Update OOjs UI to v0.2.2

Change-Id: Ia4222ae10b8ff4496faa0327270b24009333f939