The fix was confirmed as part of the specification.

Implement option B for NAL unit header syntax.
NOTE: Neither the JVET-O0129-v2 or the JVET-O2001-vEJVET-O2001-vE documents specify a nal unit type NAL_UNIT_VPS, and this nal unit type is required. In this implementation NAL_UNIT_VPS is defined to be 25.

Software implementation for N0278:
1. Added VPS encoding in encoder
2. Add new project StreamMergeApp to N-to-1 bitstream merge
3. Changed decoder to support only decoding the specified layer stream

diverges from current draft, thus using EMULATION_PREVENTION_FIX macro to mark changes

includes:
- rename flag HandleCraAsBlaFlag to HandleCraAsCvsStartFlag
- changes of NAL unit types (reduced number)
- profile_tier_level and general_constraint_info structures