Changes

Add telnet or rlogin support to wwivd. (#1361)

Start of experimental telnet support from WWIV.

Add a new bbs entry into the matrix list, and instead of the binary
command to run (i.e. bbs -XT -H@H -N@N), use the form:

     @telnet:HOST:PORT

   Example: @telnet:localhost:2300

Right now most of the other commands don't matter, but do know that
this will "tie up" a node number so set start/end to something like
1 and 10.  Also the @H and @N parameters don't really mean anything
in here, nor does working dir ssh command, etc.
Here's what I have in wwivconfig:
┌─────────────────────────────────────────────── Matrix Config: mystic ┐
│            Key: m                                                    │
│           Name: mystic                                               │
│    Description: Mystic BBS (MIS)                                     │
│    Working Dir:                                                      │
│ Telnet Command: @telnet:localhost:2300                               │
│    SSH Command:                                                      │
│   Require Ansi: No                                                   │
│     Start Node: 1                                                    │
│       End Node: 10                                                   │
│     Local Node: 0                                                    │
└──────────────────────────────────────────────────────────────────────┘
Fixes #1361

update readme