--tinymux

Support for TinyMUX (see: http://wiki.tinymux.org/index.php/COLOR256 ).
This is tested and works without problem, but I wouldn't mind rewritting it one of these days, in order to generate the exact same image output with different code. This is mainly driven by the fact that some clients (telnet included) only support 4096 characters in a line input. Since I don't know when/if I'll be able to do that rewrite... here's a pull request anyway.