wercker.yml that updates the android box with the android-7 part of the sdkbox: wercker/android

wercker.yml

box: wercker/android
# Build definition
build:
  # The steps that will be executed on build
  steps:
    - script:
        name: show base information
        code: |
          gradle -v
          echo $ANDROID_HOME
          echo $ANDROID_BUILD_TOOLS
          echo $ANDROID_UPDATE_FILTER
          
    - wercker/android-sdk-update:
        filter: android-7
    # A step that executes `gradle build` command
    - script:
        name: run gradle
        code: >
          gradle --full-stacktrace -q 
          --project-cache-dir=$WERCKER_CACHE_DIR build