Docker image update (#867)

* update

* buildtools and gradle bump

Author: Langston Smith

circle.yml

@@ -20,7 +20,7 @@ workflows:
 jobs:
   primary:
     docker:
-      - image: mbgl/feb0443038:android-ndk-r17
+      - image: mbgl/61abee1674:android-ndk-r18
     working_directory: ~/code
     environment:
       JVM_OPTS: -Xmx3200m

gradle/dependencies.gradle

@@ -4,7 +4,7 @@ ext {
             minWearSdkVersion: 23,
             targetSdkVersion : 27,
             compileSdkVersion: 27,
-            buildToolsVersion: '27.0.3'
+            buildToolsVersion: '28.0.3'
     ]
 
     version = [
@@ -51,7 +51,7 @@ ext {
     pluginVersion = [
             checkstyle         : '8.2',
             firebase           : '1.1.1',
-            gradle             : '3.1.0',
+            gradle             : '3.2.0',
             gradlePlayPublisher: '1.2.0'
     ]
 

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
-#Thu Apr 26 12:58:02 PDT 2018
+#Tue Sep 25 11:48:26 PDT 2018
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.4-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.6-all.zip