CI: Require XCode version 8.1 with swift 3.0.1 support
CI: Require XCode version 8.1 with swift 3.0.1 support

3DprintFIT/octoprint-ios-client,3DprintFIT/octoprint-ios-client,3DprintFIT/octoprint-ios-client,3DprintFIT/octoprint-ios-client,3DprintFIT/octoprint-ios-client