Minor changes to packet 0x03 and add new send function.
Add encryption support for Tethealla clients.

These will be the executables distrubuted to people to connect to
the server once it's up, but the encryption key/initialization only
worked for the official Sega client.
Remove dead encryption code.

Encryption is now handled by the modified version of fuzziqer's
library, so these functions no longer need to be here.
Cleanup and add comments.