Use signtool from Windows Driver Kit 8
Misc fixes.
Revert "Misc fixes."

This reverts commit 32f6477cdc3fb13ff98f33181cfdcc1a190a8fb1.
Portability fixes.
Silence some misterminated file warnings.
Use the officially-sanctioned method to invalidate a GTK+ window from any thread.
Fix omission of request callback, which was causing null ptr to be returned.
Need to choose a windows version to get threading support.
Add contents scale change event (handles NPNVcontentsScaleFactor).
Remove browser detection which broke on IE11
fix weak_ptr checking in JSObject, wrap InvokeAsync usage in catch
Fix for a crash during shutdown
fix for FB-254

Just one class registration is sufficient.
Use OSX-SDK on Mac OSX 10.9
fix missing gboolean/gpointer when building with FB_GUI_DISABLED