Add arcfour from nettle library

	* Makefile.am: Add nettle-arcfour
	* Makefile.in: Regenerate
	* analysis/simulator.in: Add nettle-arcfour
	* configure: Regenerate
	* configure.ac: Add nettle-arcfour
	* src/nettle-arcfour/Makefile.am: Create
	* src/nettle-arcfour/Makefile.in: Regenerate
	* src/nettle-arcfour/arcfour.c: Import arcfour from the nettle library
Add cast128 from nettle library.

	* Makefile.am: Add nettle-cast128
	* Makefile.in: Regenerate
	* analysis/simulator.in: Add nettle-cast128
	* configure: Regenerate
	* configure.ac: Add nettle-cast128
	* src/nettle-cast128/Makefile.am: Create
	* src/nettle-cast128/Makefile.in: Regenerate
	* src/nettle-cast128/cast128.c: Import cast128 from the nettle library