Make navigation strip functional

[TheGrandVizier]

The navigation strip that indicates to the user where in the process he is should be functional and clickable to make it easier for a user to return to a previous phase and make adjustments.

Repro:

1. Start the process and arrive at payment phase.
2. Click on the navigation bar to go back to a previous page.

Expected:

1. User navigates to desired phase if that phase has already been completed.

Actual:

1. Nothing happens, bar is not interactive.

[ibanner]

Sorry, mea culpa :-/