Feature: Add/Respect option to use trailing comma

Kotlin 1.4 supports trailing commas. They can be enabled in Idea's Settings->Editor->Code Style->Kotlin->Other.

It would be great if the plugin would respect the setting and generate trailing comma, so instead:
```kotlin
User(
  name = "",
  phone = "",
  address = ""
)
```
it would generate
```kotlin
User(
  name = "",
  phone = "",
  address = "",
)
```