Update dependencies

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:2.1.2'
+        classpath 'com.android.tools.build:gradle:2.2.2'
         classpath files('gradle-witness.jar')
         // bintray dependency to satisfy dependency of openpgp-api lib
         classpath 'com.novoda:bintray-release:0.2.7'
@@ -15,7 +15,7 @@ buildscript {
         classpath 'org.kt3k.gradle.plugin:coveralls-gradle-plugin:2.6.3'
 
         // allows to check for lib updates with "./gradlew dependencyUpdates -Drevision=release"
-        classpath 'com.github.ben-manes:gradle-versions-plugin:0.12.0'
+        classpath 'com.github.ben-manes:gradle-versions-plugin:0.13.0'
     }
 }
 
@@ -26,7 +26,7 @@ allprojects {
 }
 
 task wrapper(type: Wrapper) {
-    gradleVersion = '2.12'
+    gradleVersion = '3.1'
 }
 
 subprojects {