Upgreded gems.

* Stick (again) to rspec < 3.0.0.
* bundle update.
Added template_options parameter to lxc type.

* Now it's possible to pass down options to the template.
* Added unit tests for the parameter.
* The user must make sure those options are properly written as I cannot
  keep track of all of them.
* The only validation check done is to make sure it's an Array.
Different list of packages for Trusty or Precise.

* Precise uses by default ruby 1.8 which requires rubygems.
* Due to Puppet using ruby1.8 by default on Precise, it doesn't reload
  the ruby-lxc bindings, so it needs two runs to actually create the
  containers.
Mods on beaker's nodes.

* Role is now default instead of master.
* Precise image uses now the box from vagrantcloud.
Make sure rubygems is there when on Precise.
Tried to overcome the ruby1.8 issue on Precise.

* Tried to get puppet installed via gems on ruby 1.9 but somehow the
  test fails, Puppet exits with code 6 so beaker complains. The catalog
  applies and the container is created. It's not clear why Puppet exits
  with failure code.
Added template_options to acceptance tests.

* For using my closest ubuntu mirror.