Handlers for app command to create and get app

handlers.go

func createApp(cmd *cobra.Command, args []string) {
	appName := args[0]
	keyPair := app.CreateApp(appName, db)
	printResult(keyPair)
}

func getApp(cmd *cobra.Command, args []string) {
	publicKey := args[0]
	keyPair := app.GetApp(publicKey, db)
	printResult(keyPair)
}

func printResult(keyPair *app.App) {
	fmt.Println("Name: ", keyPair.Name)
	fmt.Println("Public Key: ", keyPair.PublicKey)
	fmt.Println("Secret Key: ", keyPair.SecretKey)
}