* Optimize template

* add test

* Optimize useless `val`
Others have been done at kotlin
https://github.com/kobylynskyi/graphql-java-codegen/issues/420

* update

* fix GraphQLRequestSerializer toString on scala.Option/Seq

* support kotlin

* fix unit test

* fix scala

* add plugin, fix doc

* Do not use empty data class

* update

* update

* add unit test.
remove tostring

* update

* update

* update

* update

* refactor

* add unit test

* support option  any where.
https://github.com/kobylynskyi/graphql-java-codegen/issues/415

* add task  with kotlin in gradle

* 🚀 supportScalaOption for primitive type

* fix

* add unit test for scala Option

* change var name

* Complete Scala test

* For kotlin, 'getUseOptionalForNullableReturnTypes' is ignored, which is compatible with the nullable semantics of any graphql.

* add unit test

* Small format error

* use case class for `XXParametrizedInput` and create apply for XXGraphQLOperationRequest

* use case class for `XXParametrizedInput` and create apply for XXGraphQLOperationRequest

* change interface method to properties

* change interface method to properties

* Optimize equals

* 1. Refactoring `toString` and `equals` methods(Simplify code bloat caused by large number of fields).
2. For Scala(after that, kotlin will do the same), the `builder` is no longer generated by default.

* rm a invalid `if`

* rm a invalid `if`