should have change event

[Derek Price]

It would be nice to have a single 'change' event to listen for rather than having to do this:

    // Register message changes to update the links.  Wouldn't a
    // 'change' event be nice?
    oEditor.on ('change', updateLinksTimer);
    oEditor.on ('setData', updateLinksTimer);
    oEditor.on ('insertHtml', updateLinksTimer);
    oEditor.on ('insertElement', updateLinksTimer);
    oEditor.on ('loadSnapshot', updateLinksTimer);
    oEditor.on ('key', updateLinksTimer);
    oEditor.on ('afterUndo', updateLinksTimer);
    oEditor.on ('afterRedo', updateLinksTimer);

Thanks.

[Frederico Caldeira Knabben]

DUP of #900