* initial commit for camera preferences and preload stream
* cleanup and add tests
* respect camera preferences on each request stream call
* return the new prefs after update
## Description:
For RTSP streams, set the `prefer_tcp` FFMPEG flag. This should resolve some of the "green feed" issues that some users are reporting, likely due to packets being lost over UDP on their network.
Resources: [FFMPEG protocols documentation](https://ffmpeg.org/ffmpeg-protocols.html#rtsp)
## Checklist:
- [x] The code change is tested and works locally.
- [x] Local tests pass with `tox`. **Your PR cannot be merged unless tests pass**
- [x] There is no commented out code in this PR.
* initial commit of streams
* refactor stream component
* refactor so stream formats are not considered a platform
* initial test and minor refactor
* fix linting
* update requirements
* need av in tests as well
* fix import in class def vs method
* fix travis and docker builds
* address code review comments
* fix logger, add stream start/stop logs, listen to HASS stop
* address additional code review comments
* beef up tests
* fix tests
* fix lint
* add stream_source to onvif camera
* address pr comments
* add keepalive to camera play_stream service
* remove keepalive and move import
* implement registry and have output provider remove itself from stream after idle, set libav log level to error
Franck Nijhof
Paulus Schoutsen
droopanu
cgtobi
Jason Hunter
Paulus Schoutsen