func (t *T) Exec(cmd ...string) (err error) {
	toRun := strings.Join(cmd, " ")
	input, err := shellquote.Split(toRun)
	if err != nil {
		return
	}
	err = execCmd(input)

	return
}
func (t *T) Exec(cmd ...string) (err error) {
	toRun := strings.Join(cmd, " ")
	input, err := shellquote.Split(toRun)
	if err != nil {
		return
	}
	err = execCmd(input)

	return
}
// Exec runs the system command. If multiple arguments are given, they're concatenated to one command.
//
// Example:
//   t.Exec("ls -ltr")
//   t.Exec("ls", FILE1, FILE2)