* Since these types are more prevalent than originally designed, it
makes more sense to remove the namespace for ease of typing/naming.
* Also add a specialised type 'bytebuf' for an array of bytes.
* This makes mapping easier to SWIG since there's no special casing for
namespaced arrays. Especially so for nested cases like
rdctype::array<rdctype::str> -> rdcarray<rdcstr>