Split logic among more hooks

This makes first wizard to remember answers from previous installation.
It detect default values for the first time.

These changes requires kafo >= 0.6.0 to work.
Update README.md
Merge pull request #5 from ares/remember_values

Remember values
Support RHEL7 as a default OS for provisioning

When staypuft host is RHEL6 then we automatically configure
RHEL7 as a default OS for provisioning.
On RHEL setup both 6 and 7
Automatic commit of package [foreman-installer-staypuft] release [0.0.14-1].
Fix RHEL7 default repo
Merge pull request #13 from ares/master

Fix RHEL7 default repo
Automatic commit of package [foreman-installer-staypuft] release [0.0.15-1].
Ensure required ports are open
Accept CIDR for netmask and convert it
Don't start configuration if installation fails
Merge pull request #17 from ares/master

Several fixes backported from devel
Automatic commit of package [foreman-installer-staypuft] release [0.0.16-1].
Fix netmask for nil values
Merge pull request #18 from ares/master

Fix netmask for nil values
Automatic commit of package [foreman-installer-staypuft] release [0.0.17-1].
Fix BZ#1102394

Set correct repo name for both EL6 and EL7
Fix BZ#1105328

Menu values can be selected only by number. Hence wrong value does
not list all values but their indices.
Fix BZ#1102706

Staypuft installer asks for Host Gateway and DHCP gateway. The first one
is used staypuft machine (if configure networking is on), the later is
used for DHCP. DHCP gateway will be used by hosts that use DHCP server
managed by staypuft.