Form controllers are now able to return something other than true or
null. Whatever is returned by the form controller will be passed on by
the form if it isn't a boolean.
When this code was written, it did not include an internal URL mapper
and each page was loaded by a PHP script. The internal URL was a recent,
mostly unfinished addition.
Base URL is now supported:
* for views, when they implement the BaseURLAware interface (a base
class that does what most views will do with that is provided -
BaseURLAwareView),
* in the menu,
* in form actions,
* in boxes (for buttons, and for the contents if the inner view
implements BaseURLAware).
