Use osfamily fact instead of operatingsystem.

The operatingsystem fact is used across the whole module.
Ensure this applies and switch from operatingsystem fact
to osfamily where needed.
Merge pull request #599 from enovance/use_os_family_fact_in_lb

Use osfamily fact instead of operatingsystem.
loadbalancer.pp: Enable HAProxy binding on 80 and 443

Currently, one can enable HA only on plain http or https
for horizon, but can't have it enabled for both at the
same time.

This commit makes configuration for horizon http and https
completly independent, one can decide to enable one and not
the other, add specific bind options for one and not the
other, etc...