Wait for response on socket when sending

It appears that signald doesn't like not being able to send something back on
the socket.

cmd/signald-cli/cmd/send.go

@@ -19,6 +19,7 @@ import (
 	"log"
 
 	"github.com/spf13/cobra"
+	"time"
 
 	"git.callpipe.com/finn/signald-go/signald"
 	"git.callpipe.com/finn/signald-go/signald/client-protocol/v1"
@@ -59,6 +60,20 @@ var sendCmd = &cobra.Command{
 			request.AttachmentFilenames = []string{attachment}
 		}
 		s.SendRequest(request)
+
+		timeout := 10
+
+		// Wait for the response
+		c := make(chan signald.Response)
+
+		go s.Listen(c)
+		select {
+		case <-c:
+			log.Println("Ok.")
+		case <-time.After(1 * time.Second):
+			// But timeout after a while
+			log.Fatalf("Timeout after %d seconds\n", timeout)
+		}
 	},
 }