fixes #777 - this enable auditing of when a host is changing its puppet class assignmetns

one limitation of this patch is that at the moment, each class change
gets its own audit record.

fixes #1029 - allows smart variables to be resolved via http get request.

this would allow to an external query to resolve a variable value to a given host.

e.g.
http://foreman/hosts/<fqdn>/lookup_values/<variable_name>

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

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

fixes #967 - bookmark fails if its name includes a "."

Version bump to 0.3

fixes #903 - Show resulting provisioning options at the Host edit screen