First pass at YP registration/configuration (#209)

* Spike: Ping YP service with instance details

* WIP: Add to the config to support YP

* Add YP response endpoint

* Handle YP errors. Use config. Off by default

* Show message about YP support on launch

* Add animated gif preview when generating thumb

* Increase quality of preview gif and only create it if YP is enabled

* Do not allow re-registration by clearing the key

* Make large and small logos actually structured

* Change log level

* Fix default YP service URL

* Point to default hostname

* Set default value for YP to false

config/defaults.go

@@ -16,6 +16,8 @@ func getDefaults() config {
 	defaults.PrivateHLSPath = "hls"
 	defaults.VideoSettings.OfflineContent = "static/offline.m4v"
 	defaults.InstanceDetails.ExtraInfoFile = "/static/content.md"
+	defaults.YP.Enabled = false
+	defaults.YP.YPServiceURL = "https://yp.owncast.online"
 
 	defaultQuality := StreamQuality{
 		IsAudioPassthrough: true,