load after the environment is loaded

it would be nice to leave the original order of things alone, so we can do load environment -> load test helpers, basically turning the railtie setting into a require / making things less involved/tied to rails startup process.

seems also dangerous to have a test-framework define a railtie + locks down all tests to have to use minitest-spec-rails, maybe I have different test frameworks and don't always want it 

should probably remove 'minitest-spec-rails' so upgraders stop loading it

@metaskills