Fix potential misaligment crash in AVX2 denoise_dct
Fix build with PIC on some systems
Fix possible crash when writing very large filler NALUs

Bitstream-reallocation function didn't handle the case of filler.
OpenCL cosmetics
Interface: if vbv-maxrate < bitrate, set bitrate = vbv-maxrate

This probably makes more sense to the user than setting vbv-maxrate = bitrate,
as before.
Add "--stitchable" option for segmented encoding

Stops x264 from attempting to optimize global stream headers, ensuring that
different segments of a video will have identical headers when used with
identical encoding settings.
Add new color primaries, transfer characteristics, matrix coefficients
x86: faster AVX2 iDCT, AVX deblock_luma_h, deblock_luma_h_intra
Tweak i16x16-delta-quant-avoidance code

Don't omit the delta quant if it'd raise the quantizer to do so; this fixes
a rare flickering issue caused by deblocking.