add packages to make ruby warden dev more pleasant
add packages to make ruby warden dev more pleasant

Signed-off-by: Maria Shaldibina <a39f51a90bfcf8ca23756ef12127e1cf20796cba@pivotallabs.com>

shashidharatd/garden-linux,cloudfoundry-incubator/garden-linux,tangfeixiong/garden,cloudfoundry-incubator/garden-linux,shashidharatd/garden-linux,cloudfoundry-incubator/garden-linux,tangfeixiong/garden,savaki/garden,tsaleh/garden,cloudfoundry-incubator/garden,cloudfoundry-incubator/garden,tsaleh/garden,savaki/garden,shashidharatd/garden-linux,shashidharatd/garden-linux