Deflect 0.13.0

• 163:
  Stereo streaming accepts side-by-side images as input.
• 161:
  DesktopStreamer OSX: the default hosts are read from a json file in the app
  bundle. This is useful for external users who want to adapt the official
  BlueBrain releases to their own needs without recompiling.
• 156:
  Deflect can be released as a Debian/Ubuntu package. Once installed,
  DesktopStreamer can be launched from the desktop's applications menu.
• 153:
  • Fix: Stream async send used LIFO queueing, not FIFO
  • Optimize concurrency of Stream asynchronous send
• 157:
  Better event registration mechanism, fixes warnings in the multi-client case.
• 154:
  On the server side, segments can be decoded to YUV images, saving CPU time by
  skipping the YUV -> RGB conversion step.
  Additionally, Stream images can be further compressed using optional
  chroma subsampling.
• 148,
  153:
  Support for streaming stereo 3D content in a frame-sequential manner.