Generalize circular mesh motion for wind energy applications with sliding/overset

[spdomin]

All the code base to generalize omega specifications with proper centroid coordinates. Currently, wind energy applications require flow in the z-direction with assumption that the centroid is zero.

Allow for a general centroid specification (user defined) with arbitrary rotation.

[spdomin]

Allow for centroids to be specified within input file for mesh motion and wind energy aux function:

commit a87f3d4