fixes #13494 - change puppet proxy for several hosts at once

This commit adds the possibility to select multiple
hosts and change the puppet proxy for them.

fixes #13440 - rename Host#model_name to #hardware_model_name

Rails 4.2 defines a model_name instance method which is used in routing
and called from link_to. Rename our model_name methods to
hardware_model_name to prevent this overlapping and causing link_to...

Fixes #13386 - Adds taxonomy parameters objects

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

fixes #12920 - allowing os parameters to be set via API

Refs #12911 - Fixing colon method calls

fixes #13430 - add missing actions to virt power manager

When rebooting a vm via power manager, this fails:

| TypeError: nil is not a symbol | /Users/f0218175/foremandev/foreman/app/services/power_manager/virt.rb:25:in
`block (2 levels) in <class:Virt>'...

Fixes #12718 - smart proxy log table

This patch adds a table with logs fetched from Smart Proxy /logs new API. It
returns latest N log entries from a simple memory buffer. The table supports
filtering by level, custom filtering and it introduces several overview...

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.