XyText-UTF8

Introduction

After some years of using XyzzyText I eventually got convinced that Xyzzy is really slow compared to xytext solutions. Probably a bit less lag, but when used in lessons people clearly noticed the filling up of lines terribly slow. So I backported my utf8 experience to XyText.

Also I noticed that whenever I needed to adapt xyXXXX to a new character set or encoding or if wanting to change the parameters for slicing, gridding, offsetting and finding the UTF8 counterpart in the internal lists was really difficult.

This is why here I'm proposing new parametrized CELL using 5 chars able to be driven by external main script.