Add support for alias actions and include a few default aliases

Add the ability to define alias actions. This way it is easier to define JavaScript for similar actions that is triggered for all these actions. An example are the commonly used new, create, edit and update actions in Rails, which will now also trigger the _form alias.

Now it is not necessary to put the same JavaScript in four actions (or create a function for it that is called in all four actions manually). This simply happens automatically.

It is possible to define controller specific and controller-wide (general) aliases.