Add PointLocatorTree unit test back
Add PointLocatorTree unit test back

Only testing the "basic" part now. Mixed dimension test coming
next.

Mbewu/libmesh,Mbewu/libmesh,Mbewu/libmesh,Mbewu/libmesh,Mbewu/libmesh,Mbewu/libmesh,Mbewu/libmesh,Mbewu/libmesh,Mbewu/libmesh