Bring new sbt services using the event stream api

removes the old sbt.js apis. Now, you have to use the new Websocket and EventStram API

```js
define(['commons/websocket', 'commons/types'], function(websocket, types){

  var stdout = ko.observableArray([]);
  websocket
    .subscribe({ type: 'sbt', subType: 'LogEvent', event: { entry: { message: String, type: "stdout" } } })
    .each(function(message){
      stdout.push(message);
    });

})
```


are the above utility functions used? I don't see where relativizeFile, escapeHtml are used in this module, or where they are exported. Though I would expect we do need them in places, such as in the file API.