Do not hard code the name of the form identification element

Like the csrf element name the form identification element name should
be publicly accessible as well.

refs #5525
Check explictly for FALSE when calling onSuccess()

This allows us to just end onSuccess() without requiring it to return TRUE
to initiate redirection.

refs #5525
Make autosubmit work in non-JS enviroments

We require forms to set autosubmit=true on elements which are supposed
to be submitted automatically now. The base form then ensures that this
works in JS environments and non-JS environments as well by applying the
right changes to the HTML.

refs #5525