Make 101-tuskar-ui re-runnable

The checks that are added are:
* if a Tuskar overcloud plan already exists, skip the tuskar API
  calls
* do not update the openstack_dashboard settings if the specified
  settings are already present

Change-Id: Idedfd2dea2a823245e749ae27e40ae4e29639726
Copy static files for packaged installs

Packaged installs result in tuskar-ui compressed static files being
placed in /var/www/horizon/static/dashboard, alongside horizon static
files.  We need to copy them over to
/usr/share/openstack-dashboard/static/dashboard

Change-Id: I369cba710c01ee09584d6f3de1c9aa7195dfcb69
Increase rabbitmq timeout

This change increases the timeout waiting for rabbitmq from 3 to 60
seconds. I've observed some instances of it taking 20-30 seconds before,
so I think we need to be more generous here.

Change-Id: I908eb75790d8b90410ed1b3fa018aec9630633d3