Chat reform: - reduce code duplication by determining the proper chat class dynamically and storing it in an nsv - move static content in the resources path. Serving them is now independent from the mounted xowiki path - get rid of the ajax url path
- rework xotcl-core chat machinery to return its responses through JSON and include information about active users - depend on xowiki instead of xotcl-core only - exploit xowiki "Comet" server push implementation when the browser supports it - reduce code duplication - drop plain HTML chat - reduce hardcoded styling - minor cleanups