rake specしたときの警告に対応

WARNING: Cucumber-rails required outside of env.rb.  The rest of
loading is being defered until env.rb is called.
  To avoid this warning, move 'gem cucumber-rails' under only group
:test in your Gemfile

上記の警告を消した
Revert "rake specしたときの警告に対応"

This reverts commit 25cd6cfdbfed05191d176029b9030c39d06a6758.
Revert "Revert "rake specしたときの警告に対応""

This reverts commit a04d3537f88bad44942ff6536996114efa856ac4.
Revert "Revert "Revert "rake specしたときの警告に対応"""

This reverts commit 784d6fb1627fe29fc2d5f6dc31f7e65f88883deb.