add a feature which creates `Default-568h@2x.png' in resource directory by `motion create' in order to support 4-inch screen by default
add a feature to support multiple resource directories

change `app.resources_dir' to accept an Array too, like:

    app.resources_dir = ["resources", "vendor/GoogleMaps.framework/Resources"]
fix variable name
fix a bug which cannot build an app when `app. xcode_dir' contains spaces

RM-40 Can't build with spaces in xcode.app path
`app.resources_dir' will be deprecated
fix a bug which does not launch iOS simulator when `app.xcode_dir' is specified a path other than the '/Applications' folder
fix a bug which iOS simulator will be re-launched  at every time with `rake'

RM-52 Should not re-launch iOS simulator at every time with `rake'