add kotlin support

app/build.gradle

@@ -1,4 +1,6 @@
-apply plugin: 'com.android.application'
+apply plugin: "com.android.application"
+apply plugin: "kotlin-android-extensions"
+apply plugin: "kotlin-android"
 apply from: "${rootDir}/jdee.gradle"
 
 android {
@@ -121,4 +123,7 @@ dependencies {
 
     // https://android.googlesource.com/platform/frameworks/opt/colorpicker
     implementation project(path: ':colorpicker', configuration: 'default')
+
+    // Kotlin support
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
 }

build.gradle

@@ -1,12 +1,14 @@
-apply plugin: 'checkstyle'
+apply plugin: "checkstyle"
 
 buildscript {
+    ext.kotlin_version = "1.3.31"
     repositories {
         google()
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.2.1'
+        classpath "com.android.tools.build:gradle:3.4.0"
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
     }
 }
 
@@ -18,7 +20,7 @@ allprojects {
 }
 
 checkstyle {
-    toolVersion '8.13'
+    toolVersion "8.13"
 }
 
 ext {

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
-#Wed Sep 26 11:20:02 UTC 2018
+#Sat May 18 11:05:12 COT 2019
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.6-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-5.1.1-all.zip