Add keepalive option to rabbitmq config

Add keepalive and other socket options to the rabbitmq config.
This instructs rabbitmq to apply keepalive to its sockets, based on the
global keepalive settings, which can be configured via the sysctl
element.

Default is for rabbitmq keepalive to be enabled.

Change-Id: I4fa26f9cab0ecfe39698a3ef5ac440e2892450d3
Check if stunnel.connect_ip is set

We already define stunnel metadata, but stunnel.connect_ip is not yet
defined. In such case empty IP is generated in ports.conf which causes
syntax error.

Change-Id: Ic85779aa06f1331c0c73a83a874a38c806bd6ad4
Merge "Add keepalive option to rabbitmq config"
Merge "Check if stunnel.connect_ip is set"