Add Edit IFRAME element to resources view

Consider adding a "gadget" attribute to the resources.xml node entry. The value of the attribute will be a URL.

The URL should point to a simple specification that gives the UI an indication on how to render it. Perhaps this is specific to editing the resources as opposed to the rendering the node information.

We should also consider adopting the OpenSocial style of defining integration.

As a security feature, should a white regex/list of allowed remote URLs be a server configuration option?

Otherwise any URL could be put in "remoteUrl" and when the user clicks an Edit button it would load it within an iframe... There are browser security measures for iframes, but admins may feel more comfortable with a way to restrict this.

I think the browser security model is fine.

also, a consequent feature request would be a remoteUrl/editUrl link for "Create Node". This could be configured per-project. Should be filed as a separate issue if desired.