Fix Travis CI configuration

Author: codinguser

.travis.yml

@@ -5,17 +5,17 @@ android:
     - platform-tools
     - tools
     - tools #not a typo. Needed for SDK update
-    - build-tools-25.0.0
+    - build-tools-26.0.1
 
     # The SDK version used to compile your project
-    - android-24
+    - android-26
 
     # Additional components
     - extra-android-support
     - extra-google-google_play_services
     - extra-google-m2repository
     - extra-android-m2repository
-    - addon-google_apis-google-24
+    - addon-google_apis-google-25
 
     # Specify at least one system image,
     # if you need to run emulator(s) during your tests