only start Candlepin *after* Qpid queues are created
Today, there is no ordering between the setup of Qpid (and its queues) and the setup of Candlepin. However, Candlepin requires Qpid to be up and the queues to be created to properly work.
In the past (until Candlepin 2.5.9), if we would make a request to Candlepin (like
GET /candlepin/admin/init) while the Qpid connection wasn't set up yet, Candlepin would let that request wait and process it when the Qpid connection succeeded.
Starting with Candlepin 2.5.10, these requests will fail as Candlepin will be in
SUSPEND mode and answer with a 503.
To make the installer more resilient, we should only start Candlepin after we have started Qpid and created all the queues.
Currently, the Katello 3.10 installer fails with Candlepin 2.5.11 with the following:
[ERROR 2019-01-31T09:50:47 verbose] '/usr/bin/wget --no-proxy --timeout=30 --tries=40 --wait=20 --retry-connrefused -qO- http://localhost:8080/candlepin/admin/init > /var/log/candlepin/cpinit.log 2>&1 && touch /var/lib/candlepin/cpinit_done' returned 8 instead of one of 
And while the call to
/admin/init is not necessary (and removed in 3.11), it would also fail when
run_init is disabled and the installer executes
foreman-rake db:seed later on.