Greatly reduces the amount of memory usage when streaming from the server by:
1. Shedding use of an internal MemoryStream
2. Using HttpCompletionOption.ResponseHeadersRead to start reading the stream without loading all of the HttpContent into memory
SettingsProvider uses IOptionsMonitor to maintain the current value of settings. This gets updates on YML file changes and since it's a single instance (instead of injecting IOptions<Settings>), consumers always have the latest values.
