fixes #322 Ability to add custom variables and multiple values resovled
in a dynamic Hierarchally order

This commits introduces the ability to define variables per puppet
class.

additionally, each class can have multiple values, depends on the host
which is requesting that variable....

splitted setting default data from the migration
this allows to add new data and modify its defaults
improved settings UI a bit more
refs #100

Fixes #1020 - edit multiple ok button

Signed-off-by: Paul Kelly <paul.ian.kelly@googlemail.com>

fixes #100 - Setting is now a ActiveRecord object

This allows users to manage foreman settings via the UI.

the UI is a bit ugly, but works :)

fixes #1009 - hostgroup should show its parent classes too

fixes #35 - Allow hostgroup nesting for puppet classes and parameters

Fixes #820 - Intel Solaris support

Signed-off-by: Paul Kelly <paul.ian.kelly@googlemail.com>

fixes #984 - Display Error on environments->classes link

fixes #976 - hypervisor name can't contain "."

fixes #973 - Error 500 when click "All Puppet Classes"