SHLWAPI IQueryAssociations helpers

[Jürgen Schmied]

> This patch implements the Assoc* functions for SHLWAPI. We need to
> decide whether to duplicate or share the code for the underlying COM
> object though (i.e. can I include the c file from the shell dir?).
Sharing code is never a good idea. Usually windows implements things on one place 
and we should do so too. The only reason for some code duplication between shlwapi 
and shell32 is ms moved some functionality from shell32 to shlwapi over time.

All the assoc-stuff belongs to shlwapi now. Shell32 uses only this services.

juergen
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juergen.schmied at debitel.net