Reads the new(ish) node*/terminal.ini file when it's changed to determine
the connected-client's terminal type/dimensions. Now reports the terminal
details in the spy form title/caption and if it's UTF-8, does a real-time
translation to CP437 (since F. Piette's terminal lib only supports CP437).
There is a bug here where if the data read from the RingBuffer is a
partial UTF-8 sequence, it isn't decoded correctly. Fix that later (?) if it
actually bugs anyone.

There's no PETSCII conversion/support added here. I expect to someday replace
this entirely (likely with something that uses cterm), so didn't want to
invest too much time into this.

But at least now spying on non-traditional ANSI-BBS clients isn't so terrible
to look at.