Feature: Add option to use trailing comma

[Pavel Sveda]

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:

User(
  name = "",
  phone = "",
  address = ""
)

it would generate

User(
  name = "",
  phone = "",
  address = "",
)

[Toshiaki Kameyama]

You can add trailing comma without option.

1. Enable User trailing comma

2. Enable kotlin.formatter.allowTrailingCommaOnCallSite

3. Fill class constructor

4. Put arguments on separate lines

[Pavel Sveda]

Thank you @t-kameyama, works great!