update Gradle and Buildtools and fix YML

Author: LenaWil

.travis.yml

@@ -5,8 +5,8 @@ jdk:
 
 android:
   components:
-    - build-tools-21.1.2
-    - android-15
+    - build-tools-25.0.2
+    - android-21
 
 before_install:
 - git clone --depth 1 https://github.com/urho3d/android-ndk.git $HOME/android-ndk-root

build.gradle

@@ -4,15 +4,15 @@ buildscript {
     }
 
     dependencies {
-        classpath 'com.android.tools.build:gradle:2.2.2'
+        classpath 'com.android.tools.build:gradle:2.3.3'
     }
 }
 
 apply plugin: 'com.android.application'
 
 android {
     compileSdkVersion 21
-    buildToolsVersion "21.1.2"
+    buildToolsVersion '25.0.2'
 
     sourceSets.main {
         jniLibs.srcDir 'libs'

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
-#Mon Nov 21 21:42:02 GMT 2016
+#Fri Oct 13 18:56:29 CEST 2017
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-2.14.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-3.3-all.zip