Update build env

build.gradle

@@ -7,7 +7,7 @@ buildscript {
 
     dependencies {
         // NOTE: Always use fixed version codes not dynamic ones, e.g. 0.7.3 instead of 0.7.+, see README for more information
-        classpath 'com.android.tools.build:gradle:2.2.2'
+        classpath 'com.android.tools.build:gradle:2.2.3'
         classpath files('gradle-witness.jar')
         // bintray dependency to satisfy dependency of openpgp-api lib
         classpath 'com.novoda:bintray-release:0.2.7'
@@ -26,7 +26,7 @@ allprojects {
 }
 
 task wrapper(type: Wrapper) {
-    gradleVersion = '3.1'
+    gradleVersion = '3.3'
 }
 
 subprojects {
@@ -47,6 +47,6 @@ project(':extern:bouncycastle') {
 // SDK Version and Build Tools used by all subprojects
 // See http://tools.android.com/tech-docs/new-build-system/tips#TOC-Controlling-Android-properties-of-all-your-modules-from-the-main-project.
 ext {
-    compileSdkVersion = 24
-    buildToolsVersion = '24.0.1'
+    compileSdkVersion = 25
+    buildToolsVersion = '25.0.2'
 }