LIB-439 added @warning to takeOff
LIB-439 added @warning to takeOff

- added a detailed warning to the takeOff method docs

ipmobiletech/ios-library,jamesstout/ios-library_LITE,jamesstout/ios-library_LITE,mikerowan/ios-library,mikerowan/ios-library,zhangqinghe/ios-library,grosch/ios-library,jamesstout/ios-library_LITE,manuyavuz/ios-library,ipmobiletech/ios-library,ipmobiletech/ios-library,manuyavuz/ios-library,zhangqinghe/ios-library,mikerowan/ios-library,grosch/ios-library,grosch/ios-library,manuyavuz/ios-library,zhangqinghe/ios-library