Per P0 reqs add launch pts + make download obvious. Also misc cpy edits.

native_client_sdk/src/doc/devguide/coding/audio.rst

 .. _devguide-coding-audio:
 
 #####
 Audio
 #####
 
 .. contents::
   :local:
   :backlinks: none
   :depth: 2
 
-This chapter describes how to use the Pepper audio API to play an audio
+This section describes how to use the Pepper audio API to play an audio
 stream. The Pepper audio API provides a low-level means of playing a stream of
 audio samples generated by a Native Client module. The API generally works as
 follows: A Native Client module creates an audio resource that represents an
 audio stream, and tells the browser to start or stop playing the audio
 resource. The browser calls a function in the Native Client module to fill a
 buffer with audio samples every time it needs data to play from the audio
 stream.
 
-The code examples in this chapter describe a simple Native Client module that
+The code examples in this section describe a simple Native Client module that
 generates audio samples using a sine wave with a frequency of 440 Hz. The module
 starts playing the audio samples as soon as it is loaded into the browser. For a
 slightly more sophisticated example, see the ``audio`` example (source code in
 the SDK directory ``examples/api/audio``), which lets users specify a frequency
 for the sine wave and click buttons to start and stop audio playback.
 
 Reference information
 =====================
 
 For reference information related to the Pepper audio API, see the following
@@ skipping 345 matching lines @@
     }
     std::string message = var_message.AsString();
     if (message == kPlaySoundId) {
       audio_.StartPlayback();
     } else if (message == kStopSoundId) {
       audio_.StopPlayback();
     } else if (...) {
       ...
     }
   }