Fixes #13386 - Adds taxonomy parameters objects

Fixes #13378 - Ensure taxonomy name length validation is called once

fixes #12669 - making sure that code which requires a new attribute doesn't break migrations

the lookup_value_matcher attribute code adds a callback which expects
the attribute to exist, but when upgrading foreman, this can be a bit of
an issue, when db:migrate touches existing hosts/hostgroups, and the...

Fixes #12949 - Allow selection of external networks as main network in Openstack

fixes #13574 - remove DB access from Setting class scope

Plugins tend to register an initialiser before config/initializers/ to
require their own Setting subclasses. This loads them before
config/initializers/foreman.rb, which calls load_defaults on each known...

fixes #11346 - on new host, nic shouldn't try to call matcher

there's no point in doing the call anyway (can, theoretically, use the
fqdn field instead of asking the host) because there shouldn't be any
lookup keys with that host's fqdn, as it's a new host....

Refs #12911 - Fixing colon method calls

Fixes #13379 - Clear host.last_report when switching to build mode

Use case:

When a server with a Puppet client is rebuilt, foreman cleans the
reports but not the "last report" field.

When you switch a host from a Puppet-enablet hostgroup to a hostgroup...

fixes #13236 - apply power operations to several hosts at once

This commit adds the ability to select multiple hosts and apply power operations
(reboot, shutdown, boot) to them.

Fixes #13107 - compute attributes has indifferent access again

During upgrade to Rails 4.1, our host#create code no longer sends attributes
into the ActiveRecord create/new initializers with indifferent access. One
of these attributes, `compute_attributes` then does not work breaking...