iOS 9.2.1 Compatibility

Thanks to Kristian @trenskow for a fabulous application and having the stones to open source it for everyone to learn and benefit from. Most devs I know would have walked away when Apple screwed them.
Merged submodule for libairfloat (sorry Kristian but submodules are annoying to work with), updated libz.tbd, disabled bitcode, enabled build only active architecture, strip debug symbols. Works on non-jailbroken iPhone iOS 6s Plus 9.2.1 as the AirPlay target of a 4th gen non-jailbroken Apple TV tvOS 9.1.1. This builds and deploys successfully with a free Apple ID, Apple Developer account not needed for personal devices. You must use at least iOS 9 and Xcode 7.
Did not change build target.
Changed NSArray in AirFloatAppDelegate.m to fix issue trenskow#50 - Custom Name Does Not Persist credit to @yfliao.
Changed AVAudioSession to work around crash when switching songs, I believe this resolves issue trenskow#38.
Added hack for return iOSDeviceID to allow multiple instances on Airflow on the same network and work around MAC address no longer available in app sandbox credit to @ataibarkai.
Fixed a couple other memory management bugs in settings.c, web request.c and webserver.c, including removing redundant socket_destroy. I believe this was causing the crash when switching from one Netflix episode to the next credit to @faisalmemon.
Changed target name for libairfloat from airfloat to libairfloat.
All ready to put on the App Store, just kidding :)