Further segment feature extensions.
This quite large check in includes the following: Merge in some code from Ronald (mbgraph.c) that scans a Gf/arf group. This is used as a basis for a simple segmentation for the normal frames in a gf/arf group. This code also uses satd functions from Yaowu. Adds functionality for coding the latest possible position of an EOB for blocks in the segment. (Currently 0-15 only, hence just for 4x4 dct). Where the EOB position is 0 this acts like "skip" and the normal coding of skip at the per mb level is disabled. Added functions (seg_common.c) for setting and reading segment feature elements. These may want to be optimized away at some point but while the mecahnism is in a state of flux they provide a single location for making changes and keep things a bit cleaner. This is still proof of concept code. Currently the tested feature set:- Quantizer, Loop Filter level, Reference frame, Prediction Mode, EOB end stop. TBD:- Add functions for setting and reading the feature data with range and validity checking. Handling of signed and unsigned feature data. At the moment all is assumed to be signed and a sign bit is coded but many cannot be negative. Correct handling of EOB feature with intra coded blocks. Testing/trapping of legal/illegal ref frame and mode combinations. Transform size switch plus merge and test with 8c8 DCT work Merge and test with Sumans Segmenation coding optimizations Change-Id: Iee12e83661c7abbd1e0ce6810915eb4ec35e2d8e