Add RDO and recon of MOTION_VAR experiment

The decision framework in enc (without obmc mv refinement) and
reconstruction at both sides is implemented.

Performance gain: 2.229/2.000/1.915% lowres/midres/hdres
Encodinig time: +13%

Change-Id: I5ab634c17d7050f15ecf5d4145626d0eaa425058
7 files changed