Add Mumble support (#1245)

vendor/layeh.com/gumble/gumbleutil/bitrate.go

@@ -0,0 +1,27 @@
+package gumbleutil
+
+import (
+	"time"
+
+	"layeh.com/gumble/gumble"
+)
+
+var autoBitrate = &Listener{
+	Connect: func(e *gumble.ConnectEvent) {
+		if e.MaximumBitrate != nil {
+			const safety = 5
+			interval := e.Client.Config.AudioInterval
+			dataBytes := (*e.MaximumBitrate / (8 * (int(time.Second/interval) + safety))) - 32 - 10
+
+			e.Client.Config.AudioDataBytes = dataBytes
+		}
+	},
+}
+
+// AutoBitrate is a gumble.EventListener that automatically sets the client's
+// AudioDataBytes to suitable value, based on the server's bitrate.
+var AutoBitrate gumble.EventListener
+
+func init() {
+	AutoBitrate = autoBitrate
+}