Adding XEP-0124 partially. This will enable HTTP-Bind support for clients.
This is for testing and debugging only. Not ready for real usage.

	modified:   c2s/Makefile.am
	modified:   c2s/c2s.c
	modified:   c2s/c2s.h
	new file:   c2s/c2s_http.c
	modified:   c2s/main.c
	modified:   etc/c2s.xml.dist.in
	modified:   util/nad.c
	modified:   util/nad.h