* IMethodRef.cs: New file - Interface that method references must

	* IMethodRef.cs: New file - Interface that method references must
	implement
	* ExternMethodRef.cs: New file - Reference to a method in another
	assembly
	* Local.cs: New file - A Local variable
	* MethodInstr.cs: New file - an instruction that takes a method
	reference operand
	* IClassRef.cs: Add method to get a method reference from a class
	reference
	* MethodDef.cs: Add ability to resolve methods before defining
	them, add max stack, locals, and entry point. Make CreateSignature
	method public and static so other classes can use it.
	* TypeDef.cs: Store methods and fields in hashtables so they can
	be easily retrieved, add method to resolve member methods.
	* TypeRef.cs: Add method for resolving member methods.

svn path=/trunk/mcs/; revision=14458