oleaut32: Fix methods relating typeinfo substructures around names, guids and friends
- Clean up method implementations to be consistent and pass tests.
- Factor out common code.
- Validate arguments.
- Correctly match szNameBuf user passed strings as case-insensitive as per documentation.
- Match method parameter identifiers to be as per documentation.
- Rewrite where required to use common helpers.
Signed-off-by: Edward O'Callaghan edward@antitrust.cc