Make sure high level retries show with -q - fixes #648

Also update the exit code documentation describing that.

rclone.go

@@ -4,8 +4,7 @@
 package main
 
 import (
-	"fmt"
-	"os"
+	"log"
 
 	"github.com/ncw/rclone/cmd"
 	_ "github.com/ncw/rclone/cmd/all" // import all commands
@@ -14,8 +13,6 @@ import (
 
 func main() {
 	if err := cmd.Root.Execute(); err != nil {
-		fmt.Println(err)
-		os.Exit(-1)
+		log.Fatalf("Fatal error: %v", err)
 	}
-	os.Exit(0)
 }