Make name of ajax.py configurable

[dbrgn]

Currently there seems to be no way to use a module with a name different than ajax.py to place the ajax functions into.

In a project I'm working on, we already have a package inside the app directory that's called ajax. This causes conflicts of course.

Please create a configuration variable for settings.py that allows the user to configure the name of the ajax functions module.

[jorgebastida]

That would be excellent. There is also a patch (not mergeable right now) #53

If anybody provide an interesting solution I would love to merge it :)