user32: Call ImmProcessKey in TranslateMessage to allow IMEs to handle key processing if they choose to.

Check that out arguments have enough levels of indirection and that they 
don't derive from void * or a function pointer.

widl: Add functions to print an error or warning message using location information to enable these to be printed accurately when a check is done after an element is parsed.

Add location information to variable automatically, since this is will 
be useful for type checking of arguments.

Add FIXMEs for the remaining ones and remove the warning for 
unimplemented attribute types since we now support all the attributes 
that we parse.

widl: Check that attributes are applicable for libraries,  modules, dispinterfaces and coclasses and otherwise issue an error.

widl: Check that attributes applied to typedefs and fields are applicable and issue an error otherwise.

widl: Check that attributes applied to interfaces, functions and arguments are applicable and issue an error if not.