Got Microsoft.VisualStudio.Settings.dll out of the VSIX

This changed fixed the MsBuild warning I was getting.  As a side bonus
it removed the Microsoft.VisualStudio.Settings.dll file from my VSIX
output.  By moving the PlatformTarget to x86 on all VS specific DLLs it
caused the VSIX task to believe the dependency was properly met and
hence no longer needed to deploy Microsoft.VisualStudio.Settings.dll