UUID binary subtypes support (#59)

Three encodings supported for legacy UUID subtype (3):
  - Java Encoding
  - .NET Encoding
  - Python Encoding

New UUID subtype (4) is also supported.

JSON Parser now understand 5 additional types:
      UUID("...")  =>  HexData(4, "...")
     NUUID("...")  =>  HexData(3, "...") in .NET GUID encoding
     JUUID("...")  =>  HexData(3, "...") in Java UUID encoding
    PYUUID("...")  =>  HexData(3, "...") in Python UUID encoding
    CSUUID("...")  =>  alias for NUUID("...")

Encoding for legacy UUID subtype can be selected from
    Options -> Legacy UUID Encoding