YUV, Y4M Output: bitdepth confusion resolved
asm: ipfilter_ss[FILTER_V_S_S_8]
pixel.h: nit
TComSlice: nits

--HG--
extra : amend_source : af706ee88ff4ab1c90fd63a4f88d43f4b41542cf
tcomdatacu: remove the for loop in InitCU(), which will never execute

partStartIdx is always zero or negative, and the numElements is also always zero or negative
the for will never executed if numElements is zero or negative, removed the for loop block in initCU()
tcomdatacu: partStartIdx is always negative, no need to have else block in InitCU()
asm code for blockcopy_sp, 32xN
asm code for blockcopy_sp, 12x16 block
asm code for blockcopy_sp, 2x4
asm code for blockcopy_sp, 2x8
asm code for blockcopy_sp, 6x8
used sse4 for 2x4, 2x8 and 6x8
asm code for blockcopy_sp, 32x64
blockcopy_sp, added 16x64 block size
asm code for blockcopy_sp, 48x64
blockcopy_sp, 48x64 changed the macro name according to width
asm code for blockcopy_sp, 64xN
blockcopy_sp, corrected number of xmm registers
asm: move _sse4 block copy function pointer assignments into SSE4 section
asm: move block copy funcdefs into blockcopy8.h