option to start/switch silently

- makes switching from within tmux seamless

config.go

@@ -27,8 +27,9 @@ type Window struct {
 }
 
 type Config struct {
-	SendKeysTimeout int            `yaml:"sendkeys_timeout"`
 	Session         string            `yaml:"session"`
+	SendKeysTimeout int               `yaml:"sendkeys_timeout"`
+	Silent          bool              `yaml:"silent"`
 	Env             map[string]string `yaml:"env"`
 	Root            string            `yaml:"root"`
 	BeforeStart     []string          `yaml:"before_start"`

config_test.go

@@ -9,6 +9,7 @@ import (
 func TestParseConfig(t *testing.T) {
 	yaml := `
 session: ${session}
+silent: false
 sendkeys_timeout: 200
 windows:
   - layout: tiled
@@ -29,6 +30,7 @@ windows:
 
 	expected := Config{
 		Session: "test",
+        Silent: false,
         SendKeysTimeout: 200,
 		Env:     make(map[string]string),
 		Windows: []Window{

main.go

@@ -102,17 +102,20 @@ func main() {
 
 	switch options.Command {
 	case CommandStart:
-		if len(options.Windows) == 0 {
-			fmt.Println("Starting a new session...")
-		} else {
-			fmt.Println("Starting new windows...")
-		}
 		config, err := GetConfig(configPath, options.Settings)
 		if err != nil {
 			fmt.Fprint(os.Stderr, err.Error())
 			os.Exit(1)
 		}
 
+		if !config.Silent {
+			if len(options.Windows) == 0 {
+				fmt.Println("Starting a new session...")
+			} else {
+				fmt.Println("Starting new windows...")
+			}
+		}
+
 		err = smug.Start(config, options, context)
 		if err != nil {
 			fmt.Println("Oops, an error occurred! Rolling back...")