Don't clobber the hostname passed to Chaosnet NCP

[larsbrinkhoff]

As discussed in #31. The seemingly small change — avoid appending ".Chaosnet.NET" to an unqualified Chaosnet hostname — had far reaching repercussions. Due to how the code was previously structured, a small local change was not possible.

All the network-specific code has now been pulled out into two files tcp.c and chaos.c, which know how to take a hostname and port/contact and make a connection. The Chaosnet host name resolution has been thrown out completely, leaving that to the NCP.

Three different use cases have been tested:

• Local Chaosnet octal node address: supdup 3150 for TT ITS, and supdup 177002 for the local subnet ITS.
• Global Chaosnet hostname: supdup es.swenson.org
• Internet hostname: supdup sv.svensson.org

[larsbrinkhoff]

Fair enough, I'll look into add some switch(es).