fixes #2377 - refresh column info after editing Medium

Fixes error in 20110725142054_add_suse_templates referencing non-existent
operatingsystem_id column.
fixes #2153 - add trusted_puppetmaster_hosts setting to permit puppetmaster access

Connections to fact + report upload and externalNodes will be permitted from
any host listed in the trusted_puppetmaster_hosts setting, bypassing the
requirement for a registered smart proxy.

Setting model updated to support empty arrays for values and defaults.
fixes #2385 - use Capybara 2.0.x for Ruby 1.8 compatibility
fixes #2389 - Add basic support for plugin config to live in separate files
Added link to host on some audit entries
fixes #2390 - Add :host_id to BMC options hash

   Also make power actions return a simple true/false instead of JSON
   and add a helper to generate the bmc urls