Fix params overflow, UTF-8 and ruby includes

[andi8086]

Here I tried to include fixes for

• The open issue with buffer overflow
• Missing UTF-8 support
• non-working ruby includes

Please note that especially the buffer check might change the original intention of the code to explicitely behave as the original hardware state machine. I have no way of checking what the original hardware does. Also, original hardware did not support UTF-8, however in modern terminal emulators, UTF-8 is a must.

I understand that the original author might not want to include these changes because of that. But everybody else, feel free to do so :)

kr