Configure build tools and android version for travis.

Author: nitzanj

.travis.yml

@@ -1,5 +1,13 @@
 language: android
 
+android:
+  components:
+    - tools
+    - platform-tools
+    - tools
+    - build-tools-25.0.2
+    - android-25
+
 before_cache:
   - rm -f  $HOME/.gradle/caches/modules-2/modules-2.lock
   - rm -fr $HOME/.gradle/caches/*/plugin-resolution/