Zero initialize parameters in the generated code. Based on a patch by
Eric Kohl.

- Calculate the size of buffer required.
- Fix a typo.
- Set the buffer start and buffer end markers.

FC_SMALL is its own type and is the same size as FC_CHAR, not
FC_SHORT.

Output IDL wchar_t types as WCHAR to avoid conflicts with the
generally incompatible Unix wchar_t.

Adjust return code EAI_NODATA to WSAHOST_NOT_FOUND, like windows does
it.

convert_eai_u2w should map from unix to windows, not the other way
round (spotted by Dominic Wise).

It is allowed to copy a SAFEARRAY with a NULL pvData, as long as
cbElements is non-zero. Add a test for this and fix the safe array
code.

CreateErrorInfo isn't a stub so don't print this in the trace
message.

Add const attributes to parameters for several functions and fix up
some formatting.

OleTranslateColor isn't a stub so don't print ":stub" in the trace
message.

Don't dereference a possible NULL pointer.

Also use the specified access rights in the open_token request.