bundler_ext initial support

This adds support for bundler_ext. The idea behind this is we want to avoid
Bundler in katello foreman builds, therefore in our RPMs we are gonna rename
Gemfile to Gemfile.in.

If Gemfile.in is found, bundler is not used and loading of dependencies is
handed over to bundler_ext which loads only system gems. More info on the
bundler_ext github page.

Please note this patch does not change Foreman default behavior. Also it was
agreed Aeolus team will rename bundler_ext's namespace - in the next version
it is gonna be BundlerExt only (wihtout Aeolus stuff), becuse now this
project is used in three other projects. I will prepare a change once this
is done.
bundler_ext require statements
fixes #2239 API v2 CRUD for locations and organizations and added nested loc/org
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
Ensures that unused API v2 routes are not added when using nested routes

refs #1988 and refs #2239
ignore .rvmrc
fixes broken build

one extra / unused test was added by mistake
fixes #2221 - non admin user can't set build flag for multiple hosts
fixes #2254 - Add STI to hosts table

Signed-off-by: Joseph Mitchell Magen <jmagen@redhat.com>
Signed-off-by: Ohad Levy <ohadlevy@gmail.com>
refs #2254 - minor fixes related to host form
refs #2254 - minor fixes related to facts import
fixed test connection for existing compute-resource.
added blank option in ovirt select template.
Do not block create and destroy volume if api version is 3.1 or later.
fixes #2224 Selecting a RHEV 3.1 template does not work properly
fixes #2163 New host installation fails with RHEV 3.1
fixes #2242 - concatenate HTML errors, don't use Array#to_s on Ruby 1.9
fixes #2222 hostgroup form can be scoped by multiple taxonomys.
fixes #2251 - adds openstack image listing

also refactor image list fetching
fixes #2252 - add supports to openstack log console