upgraded build tools and gradle file

.travis.yml

@@ -5,9 +5,8 @@ android:
   components:
     - platform-tools
     - tools
-    - build-tools-26.0.1
+    - build-tools-26.0.2
     - android-25
-    - extra-google-m2repository
     - extra-google-google_play_services
   licenses:
     - '.+'

build.gradle

@@ -3,10 +3,6 @@
 buildscript {
     repositories {
         jcenter()
-        mavenCentral()
-        maven {
-            url 'https://maven.google.com'
-        }
     }
     dependencies {
         classpath 'com.android.tools.build:gradle:2.3.3'
@@ -18,19 +14,26 @@ apply plugin: 'com.android.application'
 repositories {
     jcenter()
     mavenCentral()
+    maven {
+        url 'https://maven.google.com'
+    }
 }
 
 configurations {
     playstoreCompile
 }
 
+ext {
+    supportLibVersion = '25.4.0'
+}
+
 dependencies {
     compile project(':libs:MemorizingTrustManager')
     playstoreCompile 'com.google.android.gms:play-services-gcm:11.0.4'
     compile 'org.sufficientlysecure:openpgp-api:10.0'
     compile 'com.soundcloud.android:android-crop:1.0.1@aar'
-    compile 'com.android.support:support-v13:25.3.1'
-    compile 'com.android.support:appcompat-v7:25.3.1'
+    compile "com.android.support:support-v13:$supportLibVersion"
+    compile "com.android.support:appcompat-v7:$supportLibVersion"
     compile 'org.bouncycastle:bcprov-jdk15on:1.52'
     compile 'org.bouncycastle:bcmail-jdk15on:1.52'
     compile 'org.jitsi:org.otr4j:0.22'
@@ -57,7 +60,7 @@ ext {
 
 android {
     compileSdkVersion 25
-    buildToolsVersion "26.0.1"
+    buildToolsVersion "26.0.2"
 
     defaultConfig {
         minSdkVersion 14

libs/MemorizingTrustManager/build.gradle

@@ -12,7 +12,7 @@ apply plugin: 'com.android.library'
 
 android {
 	compileSdkVersion 25
-	buildToolsVersion "26.0.1"
+	buildToolsVersion "26.0.2"
 	defaultConfig {
 		minSdkVersion 14
 		targetSdkVersion 25