Make Kick part of the Client interface.

All clients implement Kick, no need for a separate interface.

group/client.go

@@ -101,8 +101,5 @@ type Client interface {
 	OverridePermissions(*Group) bool
 	PushConn(g *Group, id string, conn conn.Up, tracks []conn.UpTrack, replace string) error
 	PushClient(id, username string, add bool) error
-}
-
-type Kickable interface {
 	Kick(id, user, message string) error
 }

group/group.go

@@ -586,10 +586,7 @@ func (g *Group) Range(f func(c Client) bool) {
 
 func kickall(g *Group, message string) {
 	g.Range(func(c Client) bool {
-		cc, ok := c.(Kickable)
-		if ok {
-			cc.Kick("", "", message)
-		}
+		c.Kick("", "", message)
 		return true
 	})
 }

rtpconn/webclient.go

@@ -1099,12 +1099,7 @@ func kickClient(g *group.Group, id, user, dest string, message string) error {
 		return group.UserError("no such user")
 	}
 
-	c, ok := client.(group.Kickable)
-	if !ok {
-		return group.UserError("this client is not kickable")
-	}
-
-	return c.Kick(id, user, message)
+	return client.Kick(id, user, message)
 }
 
 func handleClientMessage(c *webClient, m clientMessage) error {