Audio Playback

In this episode we implement one of the core functions of a podcast player: playing audio! Using AVPlayer we load up the track and observe its progress so we can update the UI to reflect time progressed, time remaining, as well as allowing the user to scrub to a position in the track.

This is a companion discussion topic for the original entry at https://nsscreencast.com/episodes/405-podcast-app-audio-playback