Massive infra provider update

Generally aimed to address failures in Jenkins, but largely an attempt to
simplify the setup of infrastructure providers and prepare these fixtures for
conversion to the new system once the infra provider classes are implemented there.

Some specifics:
- verify button and related methods are now validate button. I was getting confused between the button and the verify password field. :(
- The bulk of work for setup_infrastructure_providers is now done in utils.providers.setup_infrastructure_provider
- Related to the last bullet, there is now a generic setup_provider function in utils.providers, but it won't be very useful until cloud providers receives similar treatment to what's been done here. I don't see setup_providers being useful in test automation, but it should be extremely handy for getting a new appliance set up for manual interaction.
- setup_infrastructure_provider now fails early in the event of authentication failure
- Pages returned by navigation fixtures are callable now, and will navigate to their fixture destination when called.

I did evil things.