* verify.c: If security is not enabled don't perform
	instance verification as 2.6 SRE/mcs can't couple with it.

	Fix System.dll build regression.

	* verify.c: Add new function to internal verifier API to check
	method instantiations.

	* reflection.c (mono_reflection_bind_generic_method_parameters):
	Check the instantiation before returning it.

	Fixes #655847

	* icall.c (ves_icall_Type_MakeGenericType): We can inflate
	into the gtd and the verifier function is not able to handle
	it.

	* class.c (mono_class_init): Check instantiations of generic
	instances.

	* icall.c (ves_icall_Type_MakeGenericType): Ditto.

	* verify.c: Add mono_verifier_class_is_valid_generic_instantiation
	to the internal API so generic instances can be checked.

	Fixes #654136

removed signal exception handlers for amd64.  need to investigate why we did this, and if it can be restored to reduce upstream divergence.

I think this is a leftover from a massi backport.  doesn't look like it's doing anything anymore, but unity3 shipped like this.