Problem: need end-to-end example

Solution: implement basic server and client stacks. These models are in
wap_server.xml and wap_client.xml, with the C code is in wap_server.c
and wap_client.c.

You can read src/wap_tutorial.c for a line by line explanation, and you
can run this to see the two sides talking to each other.

For now the only commands the client API implements are START and STOP.
The server does nothing with these right now. However you can see the
placeholders in wap_server.c.