rc: Bug fixes for ABR.

remove uninitialized local variables and use values from cfg.param.rc as required.
ratecontrol: use cfg->param.frameNumThreads directly; nit cleanups
Eliminating decreament in pointer index in weightp primitives


could have been a source of possible crash
encoder: auto-padding to min CU size and set conformance window
ratecontrol: consistent comment style
remove reduce register copy in FILTER_H4_w2_2 and FILTER_H4_w4_2 (update for linux build error)
cleanup: remove unused getNumberOfWrittenBits() from TEncBinCABAC::getNumWrittenBits()
cleanup:remove unused base class TEncBinIf
cleanup: merge header operator from TEncCavlc into class TEncSbac
cabac: improvement performance by use negative cabac counter
Merge with stable
intra-sse3.cpp: replace intraPredAng8x8 vector class function with intrinsic
intra-sse3.cpp: replace intraPredAng32x32 vector class function with intrinsic
intra: move 32x32 angular prediction function into non-vector portion
intra: rename intra-sse3.cpp to intra-ssse3.cpp
pixel: converted some sad_avx2 vector class functions to intrinsic
slicetype: calculate weighted frame costs for Aq