Configurable versions for gradle/kotlin/android plugin

[jmfayard]

Hello, I wanted to fix indentation & update to Kotlin 1.1.60 ; android.gradle 3.0.1 In the meantime, I fixed the unit tests and clarified the main class

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Update: the PR adds three parameters to the config

{
  "gradleVersion": "4.3.1",
  "androidGradlePluginVersion": "3.0.1",
  "kotlinVersion": "1.1.60",
}

[borisf]

Hi @jmfayard thanks, can you resolve the conflicts so we can merge it

[jmfayard]

@borisf done

[NikitaKozlov]

LGTM

[borisf]

@jmfayard can you please resolve conflicts for us to merge

[jmfayard]

@borisf conflicts resolved