Based on a patch by Eric Kohl.

- implement a helper to decode sequences of like types
- use helper functions wherever applicable when decoding
- correct "expected" vs. "got" usage in tests
- fix a few other small bugs

SetPixelShader.

Update cubetexture so that names constants instead of numeric
constants are used for the facetype and also add some additional
checks where facetype is passed as a parameter to the function.

Added support for opening devices directly with the server when they
don't correspond to a Unix file.

- Include the header file for the functions implemented in typegen.c.
- Generate proc format for FC_ERROR_STATUS_T type.

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.