option to draw legend using annotations

[jbfaden]

I've wanted to be able to draw legends using annotations, and I started this today thinking it would be easier to do than it is. The idea is you should be able to replace the legacy legend using an annotation with text like:

"!(painter;legend;renderer=1)<br>!(painter;legend;renderer=2)" 

The problem is connecting the legend to the renderer, and also adding a control for it to the GrannyTextEditor.

[jbfaden]

This item should be clickable, setting focus to the referent renderer.

[jbfaden]

See also https://sourceforge.net/p/autoplot/feature-requests/804/ a script which converts a Das2 legend into an annotation.