Remove Mis-located and Duplicated Code Example
Remove Mis-located and Duplicated Code Example

```kotlin
prefs.edit {
  putString("first_name", "Andrew")
  putString("last_name", "Chen")
  remove("age")
}
```
yongjhih/kotlin-android-extensions,yongjhih/kotlin-android-extensions,yongjhih/kotlin-extensions,yongjhih/kotlin-extensions