add a dummy rails engine to the test directory to test the ember generators on rails engines
add a new test helper to be used on the generator tests for rails engines; add dummy_engine/config/engine.rb to boot the engine into the test environment
add the dummy_engine/tmp dir to the .gitignore file; also add .swp and .swo for vim
add tests asserting files are properly created with ember:bootstrap generator in a rails engine. Use the ENGINE_PATH constant to determine if generator command was called from a rails engine and get it's name
add test for bootstrapping a rails engine with custom app name
specify in the test descriptions that the tests apply to rails engines