Segment Features with 8x8DCT.
Temporary check in to turn off other segment features tests when #if CONFIG_T8X8 is set as the assignment of MBs to differnt segments in each case will conflict. The 8x8 code will be modified to use the new segment feature method properly in a later check in. Increase bits allowed for EOB end stop marker to 6 ready for 8x8. Change-Id: I4835bc8d3bf98e1775c3d247d778639c90b01f7f