Add travis CI support

Author: wangmengyan95

.travis.yml

@@ -0,0 +1,31 @@
+branches:
+  only:
+    - master
+
+language: android
+sudo: false
+
+android:
+  components:
+    - build-tools-21.1.1
+
+    - android-22
+
+    - extra-android-support
+    - extra-android-m2repository
+
+    - sys-img-armeabi-v7a-android-22
+
+before_script:
+    - echo no | android create avd --force -n test -t android-22 --abi armeabi-v7a
+    - emulator -avd test -no-skin -no-audio -no-window &
+    - android-wait-for-emulator
+    - adb shell input keyevent 82 &
+
+script:
+    - ./gradlew clean connectedCheck --info
+
+cache:
+  directories:
+    - $HOME/.gradle
+    - $HOME/.m2/repository