[kupu-dev] Undo functionality

[Guido Wesdorp]

Hi!

A while ago, someone asked me to implement 'proper' undo/redo for Kupu. 
I implemented the first bits, and then the requester didn't reply 
anymore, so I never got round to implement it in full, but fortunately 
some other customer now showed interest too and allowed me to complete 
the last bits (well, mostly, it still could use some tests and docs...).

In other words: there is now full undo/redo support (so not just for 
execCommand actions, but for everything) in Kupu. It's easy to enable: 
just include the 'jsincludes' part of the 'undo' feature in your head 
part (make sure to also update include.kupu) and add the following lines 
to your kupuinit.js:

var undotool = new KupuUndoTool('kupu-undo-button', 'kupu-redo-button');
kupu.registerTool('undotool', undotool);

It's already enabled in the default (demo) file, so to try just open 
common/kupu.html (after running 'make', if you hadn't done so already).

Hope you find it useful, if you have questions or remarks, feel free to 
send me an email...

Cheers,

Guido