Refactor world_frame_conversions to use Eigen vectors and Matrices

[jskhu]

world_frame_conversions is currently using arrays to manipulate world frame conversion. Need to update them to use Eigen instead.

[navganti]

@jskhu was this resolved in #272?

[jskhu]

No, world_frame_conversions still use arrays: https://github.com/wavelab/libwave/blob/master/wave_geography/src/world_frame_conversions.cpp#L42