user story #2069: create compute_id_lookupbyip facter

First step to create a better vhost lookup is to be able to identify
the current compute id value so that other facters like
'compute_vhost_name' can be created that lookup values using cloud api's
for public ip and or dns names defined for those ip's.

1. compute_id_lookupbyip, this uses the current servers ipaddress and
   searches for a server matching the same private ip.  If found
   returns the server id.

2. compute_public_ip, this uses compute_id_lookupbyip. If found
   returns the servers public ip.

3. compute_dns_name, this uses compute_public_ip.  If found
   returns the servers dns 'A' record name.

4. compute_vhost_name, this uses other facters to calculate
   a vhost name.

NOTE: all these functions will require a FOG_RC creds from maestro.

Change-Id: Ied56ba14e7723ea588374fbf1417c7388adf0d8d