Update Kotlin to version 1.2.30

Change-Id: I83425262c10837e8dc52d34b0527f6d20e838a80
diff --git a/build.gradle b/build.gradle
index f857f9e..74bf30f 100644
--- a/build.gradle
+++ b/build.gradle
@@ -36,7 +36,7 @@
     joptSimpleVersion = '4.6'
     jsonSimpleVersion = '1.1'
     junitVersion = '4.12'
-    kotlinVersion = '1.2.0'
+    kotlinVersion = '1.2.30'
     protobufVersion = '3.0.0'
     smaliVersion = '2.2b4'
 }