feat: add kotlin support (#896)

Co-authored-by: Joshua Chandler <joshchandler88@gmail.com>

bin/templates/project/build.gradle

@@ -19,16 +19,16 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
 buildscript {
+    ext.kotlin_version = '1.3.50'
     repositories {
         google()
         jcenter()
     }
-
     dependencies {
+        classpath 'com.android.tools.build:gradle:3.5.3'
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
-
-        classpath 'com.android.tools.build:gradle:3.5.3'
     }
 }