Added lib/edraw which is an electron library for drawing
Added the edraw header
The basic edraw library is usable now
Fixed the comment in lib/edraw.h
Fixed up edraw and mkfile
Removed the rectangle type.

Image now requires the four coordinates to make up the rectangle.
added edraw to chicanery
Added rgb2cmap support
Added a function to translate default colors

In Plan9Port there are a number of default colors that are useful. I've added a
function which is a very basic interface which translates a numeric index to
one of these colors. I need to add in language support for name => numeric
value.
Added basic screen drawing support