Remove unneeded reference to top-level namespace in home_controller
Dry up and speed up contexts and their specs
Tag all feature specs as 'slow'

Note: to speed up the tests, start zeus first,
then prefix all following commands with `zeus`

* to run only fast tests:
  `rspec -t ~slow spec`

* to run only slow tests:
	`rspec -t slow spec`

* to run all tests except the ones that need selenium:
	`rspec -t ~driver:selenium spec`

* to run slow tests, except the ones using selenium:
	`rspec -t slow -t ~driver:selenium spec`