[Material Design] 호환성 유지

- 호환성 유지

원문 - https://developer.android.com/training/material/compatibility.html#CheckVersion

// Check if we're running on Android 5.0 or higher
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
    // Call some material design APIs here
} else {
    // Implement this feature without material design
}