0.5.1 Release

Fixes for several different hanging scenarios.

Changes:

• Added tzdata to image to allow setting timezone with TZ env var
• Removed unused SharedArray python package
• Remove fps config value for setting expected framerate of the camera
• Skip frames in capture thread when needed to avoid filling plasma store
• Handle plasma store failures
• Fix race condition on detection process watchdog checks
• Move ffmpeg process to separate thread and communicate with a queue
• Ensure frames are cleaned up from plasma store
• Resize debug view based on actual aspect ratio of the frame
• Add frame_time for each step in processing in /debug/stats

Docker image is available with docker pull blakeblackshear/frigate:0.5.1