fixes #2275 - include ThreadSession::Cleaner only once

Foreman::ThreadSession::Cleaner was included in Taxonomy concern,
which postponed the session clearing (that should be the first thing
to happen in filters) to phase after :authorize filter, effectively...

fixes #2277 - adds spice html5 support

This also adds a newer version of the web socket proxy (where we
probably need to use an external package instead of vendor it).

we still allow users to use the old XPI based spice client (which would
ensure end to end security as well) via a 'new window' button....

fixes #2269 - Add gettext framework to foreman.

This patch adds a gettext based localization framework to the Foreman. This is done by adding the fast_gettext and gettext_i18n_rails gems along with their depdencies. An example translation is done to the login page and the users controller....

fixes #2202 - add all unassigned actions to appropriate permissions

fixes #2222 hostgroup form can be scoped by multiple taxonomys.

fixes #1988 - CRUD Actions for nested parameters for host, domain, hostgroup, os

e.g.

GET /api/domains/6/parameters
POST /api/hosts/6/parameters
PUT /api/hostgroups/6/parameters/100
DELETE /api/operatingsystems/6/parameters/100

fixes #2239 API v2 CRUD for locations and organizations and added nested loc/org

Feature: #686 - Hosts can inherit environment from hostgroup

Using Apipie versioning features and Maruku for markdown

Apipie switched from Redcarpet to Maruku to avoid crashes of the C
Extension. No further need of compiling anything to get markdown support.

API now allows for search of usergroups