* obs-frontend-api: add the event of saving replay buffer
Add OBS_FRONTEND_EVENT_REPLAY_BUFFER_SAVED as given by RFC 33
* UI: Emit the replay buffer saved event to the api
Send the OBS_FRONTEND_EVENT_REPLAY_BUFFER_SAVED to api (as in rfc33)
* docs/sphinx: Add replay buffer saved event
Documentation provided for OBS_FRONTEND_EVENT_REPLAY_BUFFER_SAVED (RFC33)
Adds support for pausing recordings. When settings are eligible for
recordings, a pause button will appear next to the recording button. If
the settings are not eligible, it will warn the user in the output
settings that they cannot pause recordings if those settings are used.
