predict: combine redundant logic paths in predInterBi()

removes weightedPredictionBi(), which is no longer called
predict: use faster unidir prediction for B frames when weighting not enabled
predict: streamline getWpScaling()
predict: remove list argument from motionCompensation(), always REF_PIC_LIST_X
predict: remove checkIdenticalMotion()

We will not insert the same reference picture into L1 and L0 at the same time,
so this check is utterly redundant.
refine deblocking filter
blockcopy_pp_32x8: avx asm code, improved 281.20 cycles -> 165.47
blockcopy_pp_32x16: avx asm code, improved 477.74 cycles -> 309.99
blockcopy_pp_32x24: avx asm code, improved 621.84 cycles -> 371.94
bloccopy_pp avx asm code: 32x32, 32x48, 32x64 improved by 803.69 -> 514.90, 1126.36 -> 655.24, 1454.09 -> 835.76 cycles
primitives: remove unused block copy primitives
cmake: remove blockcopy-sse3.cpp
vec: remove idct8, we have SSSE3 assembly for it
vec: make a note for why we keep some of the remaining vector routines
Changed FrameEncoder::m_tld to a pointer and set it to one of Encoder's ThreadLocalData instances.

This uses less memory since m_tld isn't used in --wpp and Encoder's ThreadLocalData instances are not used in --no-wpp
Also there was a small performance increase on my system
Backed out changeset: eb011fa1d2d8
Backed out changeset: 940cec3bf0b4

This commit causes hash mismatches in vc11 x86_64 Release
mode consistently, when lft is enabled. Stack/heap corruption
likely.
encoder: rename cuCoder to analysis for better clarity

the data type of cuCoder changed from TEncCu to Analysis weeks ago

--HG--
extra : rebase_source : 87ac13088486f24625d80317fd9dbb4c6b1a27a8
predict: inline single call of predInterBi()

--HG--
extra : rebase_source : a5d10add90dc4d4fd8d856955315d7d8ce327318
predict: inline predInterUni(), getWpScaling() and simplify motionCompensation()

After this refactor, motionCompensation no longer needs the cu parameter. It
was only used to pass to another member function to gain access to cu->m_slice
which is now a member variable.

This refactor removed a number of arguments to addWeightBi and addWeightUni
which were always member variables.

--HG--
extra : rebase_source : 0cba55a31876374d3879e4bc568e0d5fa384f047