enable dynamic AU size in decoder
Add arm64 neon code for Satd.
    add pskip MD functions
Merge pull request #925 from lyao2/pskip_func_commit

add pskip MD functions
Merge pull request #923 from zhilwang/satd-arm64

Add arm64 neon code for Satd.
Merge pull request #916 from huili2/dynamic_dec_au_size

enable dynamic AU size in decoder
add ref-original frame assigment
Merge pull request #924 from ruil2/expand_pic_1

resolve unit test warnings
Merge branch 'master' of https://github.com/cisco/openh264 into expand_pic_1