Add Travis or some other CI

[RyanNewsom]

This will make it easier for you guys to manage contributions.
Here is a script I am using for my own project using Travis:

# Emulator Management: Create, Start and Wait
before_script:
  - echo no | android create avd --force -n test -t android-22 --abi armeabi-v7a
  - emulator -avd test -no-audio -no-window &
  - android-wait-for-emulator
  - adb shell input keyevent 82 &

language: android
android:
  components:
    # Uncomment the lines below if you want to
    # use the latest revision of Android SDK Tools
    # - tools
    # - platform-tools

    # The BuildTools version used by your project
    - build-tools-26.0.2

    # The SDK version used to compile your project
    - android-26
    - android-22

    # Additional components
    - extra-google-google_play_services
    - extra-google-m2repository
    - extra-android-m2repository
    - addon-google_apis-google-19

    # Specify at least one system image,
    # if you need to run emulator(s) during your tests
    - sys-img-armeabi-v7a-android-22

script:
  # By default Travis-ci executes './gradlew build connectedCheck' if no 'script:' section found.
  - ./gradlew build
 # Unit Tests
  - ./gradlew testDebugUnitTest
 # Instrumentation Tests
  - ./gradlew connectedCheck