A class that exposes a simple in-memory representation of a document of
MsgPack objects, that can be read from and written to MsgPack, read from
and written to YAML, and inspected and modified in memory. This is
intended to be a lighter-weight (in terms of memory allocations)
replacement for MsgPackTypes.
Two subsequent changes will:
- switch AMDGPU HSA metadata to using MsgPackDocument instead of MsgPackTypes;
- add MsgPack AMDGPU PAL metadata via MsgPackDocument.