self-registerable standard DLLs

[John K. Hohm]

I noticed that the attempt to test comcat.dll on Win98 failed because
DllRegisterServer is a stub returning E_NOTIMPL.  I have added the
registry entries for the component categories manager to winedefault.reg,
which should suffice for normal Wine installations.  Despite this, is it
generally acceptable to have actual code to register/unregister a standard
COM server DLL in its Dll[Un]RegisterServer?  It would be redundant for
normal Wine, but hey, it's not big or complex.