Adopt rabbitmqadmin in integration tests

[jjasghar]

It seems we can something like:

cd /usr/local/bin 
sudo wget https://raw.githubusercontent.com/rabbitmq/rabbitmq-management/rabbitmq_v3_5_0/bin/rabbitmqadmin 
chmod +x rabbitmqadmin 
cd - 
rabbitmqadmin -H localhost -u guest -p mypass list vhosts
/root
+------+----------+
| name | messages |
+------+----------+
| /    |          |
+------+----------+

to add the rabbitmqadmin as another recipe. with this we can add serverspec tests around running rabbitmqadmin and in turn test rabbitmq how you would officially from rabbitmq.

This shouldn't be too much work, but I wanted to capture it here so we can revisit it at a later date.

[tas50]

Inspec

[michaelklishin]

In most cases it wouldn't be any different from using rabbitmqctl, rabbitmq-diagnostics, and so on but let's keep this open, maybe it would come handy in 6.0.