BitStream: Live streaming

10/4/2017

RTMP upstream improvements and advanced settings.
Auto-detect optimal audio encoder delay.
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* Twitch Chat Head! See the chat, set text size, or end the broadcast using the always on-top bubble.
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* Twitch updates: emotes saved to local database on-demand, no longer eating 20 MB of RAM; chat auto-scroll toggle; WebSocket fixes;
* Small renderer tweaks
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* YouTube 2160p (4K) + SuperChat
* Menu: lock and remember camera rotation; device rotation detector on the fly