libctf: type copying

libctf: type copying

ctf_add_type() allows you to copy types, and all the types they depend
on, from one container to another (writable) container. This lets a
program maintaining multiple distinct containers (not in a parent-child
relationship) introduce types that depend on types in one container in
another writable one, by copying the necessary types.

libctf/
	* ctf-create.c (enumcmp): New.
	(enumadd): Likewise.
	(membcmp): Likewise.
	(membadd): Likewise.
	(ctf_add_type): Likewise.