switch to c++ implementation
merge master
moved DPB functions into DPB class as member functions
copy image in one go if strides match
move zeroing of byte counter after releasing NAL units
add extern-C markers around windows conditions for c++ compilation
merge master branch
make init/free functions of DPB its constructor/destructor
move set/get_mv_info to image structure
remove obsolete function get_img_mv_info
move NAL buffer handling into NAL_unit class
remove now-obsolete rbsp_buffer class
remove old dead code
rip out NAL parsing into its own class
add new nal-parser class
implement de265_decode using new nal-parser
Revert "make init/free functions of DPB its constructor/destructor"

This reverts commit 71e22fd6deaf0ff5b718b4a785d4df72447b7499.
skipped-byte processing now private to NAL_unit/parser
remove obsolete nal-parser::clear function
NAL_queue now using std::queue