Import and other Controllers: Compatibility fixes for modified wizardHeader.tpl

We modified wizardHeader.tpl quite a bit for Quest - and added several
control variables to the steps array. Now we need to fix the
Controllers for Import Contacts, Export Contacts, Import Contributions
and Import Activity History (any other wizards?) so they
define these additional items:

valid => 1 (for all steps)
step => 1 (e.g. true for all steps)
stepNumber => $value (assign the step number)
collapsed => 0 (eg false for all steps)

Also - we're currently passing the link item (href), but shouldn't for
the steps in these import
wizards as we don't want the wizard steps to be clickable, e.g....
link => NULL (for all steps)

You can verify the current "problem" by noting that the past/current/future
step styles aren't showing properly in the wizard "bar" AND the "boxes" are
clickable (which they shouldn't be - except for the Quest pre-app).