-For the binary "installation", look for the DLL files with their file
names consistent with the ones that are generated with the respective
Visual Studio projects.
-Remove any stray GDK DLLs that were left over from a Broadway-enabled
GDK when building a non-Broadway-enabled GTK+ binary set.
Update the gtk-install-bin property sheets so that it does not "install"
the wrong GDK DLL/LIB when building a broadway-enabled GDK
when the non-Broadway GDK had been previously built.
Add the Visual Studio 2010 projects to build the GDK Broadway backend, just
like the Visual Studio 2008 project files in the last commit. Similarly,
split up the property sheets so that they are easier to maintain and can
be made more flexible for different build types. Also remove some unneeded
stuff from some of these items.
Also, fix the filter file completion for GTK, as a source file was excluded
for that and this was overlooked as it seemingly did not cause any trouble.