launches the simulator that is in the xcode version set by xcode-select

Using `activate application "iPhone Simulator"` in AppleScript was launching a different version of Xcode that was not set as the default with `xcode-select`

In my case, it was launching 5.1 Developer Preview instead of 5.0.2

This PR fixes that, but I honestly haven't tested against Xcode <5.

Do you know if the iPhone Simulator file is in the same path for Xcode 4?

Thanks!