The vertex pathfinder was implemented directly in CCmpPathfinder,
instead of being a separate helper like the hierarchical pathfinder or
the long pathfinder.
This moves it to its own helper VertexPathfinder, which gets us ready
for D14 and pathfinder threading. Some struct definitions need to be
moved around.
Differential Revision: https://code.wildfiregames.com/D1855
This was SVN commit r22253.
wraitii
809f297707