Layout now has a callback to be executed after template has been loaded and rendered.
RawData didn't have a parse() method like Backbone collections do.

Datasource needs it for cloning / initial data population.
Headless browsers like phantom.js have problems with fade outs of the loading animation.
Ignoring already detached widgets in the loading animation algorithm.
Accounting for require.js weird behaviour after we change window.location in order to redirect to login.
No need to reference layout using an instance variable.
Always passing global channels to controllers in their channel mapping.
Add method for finding whether a DOM element has vertical scroll or not.
Removed obsolete comment.
Accounting for the case where detached widgets are trying to initialize - because their parent was killed before they had the chance to initialize.
Prevent the same widget from being initialized twice by marking it as processed earlier and synchronously.

This can happen due to the flow of mutation events:
* parent DOM element is picked up, so child is initialized
* child DOM element is picked up, so child is initialized again
destroy() of a widget should never fail.
Using Utils.deepClone() instead of _.clone.
Making sourceMappingURL more compatible with Chrome.
parseJSON() breaks in newer versions of jQuery for undefined params.
Replacing uberdelayed class with data-delay=true/false attribute.

Even though technically it's the same thing, every class modification
triggers a repaint cycle of the browser, so we should not use CSS
classes for meta-data from now on.
Removing profiler from Mozaic core. We never really used it.
Making sure that datasource doesn't react before other subscribers to /new_widget.

In order to do this, we're using the multi-event capability of the
Backbone.Events event emitter, which will call all the callbacks for
the second event (/widget_ready) after the callbacks for the first one.
Add callback for post-processing data after it arrives in a channel.

Regardless of the reason for which data has appeared.
Small style changes.