Description

• Add support for eRTMP multitrack video configuration URL to rtmp-services

Motivation and Context

• Twitch/Amazon IVS uses server side configuration for eRTMP Enhanced Broadcasting/multitrack video stream configuration, so users don't have to manually configure renditions being sent.

• ertmp_configuration_url (and ertmp_configuration_name) are exposed in the service json configuration to allow other services to adopt the same configuration mechanism without additional code changes

How Has This Been Tested?

• This is in use in the Twitch Enhanced Broadcasting Beta

Types of changes

• New feature

Checklist:

• My code has been run through clang-format.
• I have read the contributing document.
• My code is not on the master branch.
• The code has been tested.
• All commit messages are properly formatted and commits squashed where appropriate.
• I have included updates to all appropriate documentation.