Replace coedit with DOM-based version

[ccotter]

In response to the issues associated with the coeditor (#166, #167, #183, #185), I've created a new version of the coeditor. Technically, the major change is that the rich text data is stored as a DOM tree as opposed to raw HTML text. This change helps performance, improves functionality, and eliminates the impossibility of the raw HTML version of converging to valid HTML (see #185).

Currently, the master branch of cowebx has two editor demos: cowebx-apps/coedit and cowebx-apps/coeditDom. The new coeditDom demo shall be tested for stability, correctness and will eventually replace coedit. This issue will track the progress of this transition.

[ccotter]

The developer server has update-to-date versions of the new editor:

http://vhost1628.developer.ihost.com:8080/coeditDom

[ccotter]

The only thing left before the new coedit can be seriously considered is keeping track of user's cursor. Right now, no attempt is made to save the cursor position when another remote user is editing the document. Unfortunately, I don't think we can use rangy. I'm trying to devise a solution though...

[ccotter]

My solution now is to have every client track each other's cursor positions/range selections. Tracking each selection range is the best way I can track a local client's selection range (I couldn't figure out how to track only a local client's range).

[ccotter]

The current status is that I don't think I'll easily be able to track cursor selection ranges...so I'm putting this issue on hold. Without the ability to remember cursor position, we should not replace the old editor with this tree based editor. In the meantime, I'll branch off the new editor, and remove it from the master branch.

I do, however, have some ideas for improving the functionality of the old editor, so I'll focus on that.

[ccotter]

I've removed coeditDom and the matching widget code from cowebx master. cowebx branch issue185 holds the coeditDom code in case we ever wish to revisit it.