Adds CircleCI Integration

- Adds CircleCI Integration for continuous integration
- Follows the [CircleCI v2.0 configuration](https://circleci.com/docs/2.0/language-android/)

.circleci/config.yml

@@ -0,0 +1,34 @@
+version: 2
+jobs:
+  build:
+    working_directory: ~/code
+    docker:
+      - image: circleci/android:api-25-alpha
+    environment:
+      JVM_OPTS: -Xmx3200m
+    steps:
+      - checkout
+      - restore_cache:
+          key: jars-{{ checksum "build.gradle" }}-{{ checksum  "app/build.gradle" }}
+      - run:
+          name: Chmod permissions #if permission for Gradlew Dependencies fail, use this.
+          command: sudo chmod +x ./gradlew
+      - run:
+          name: Run build
+          command:  export TERM=${TERM:-dumb} && ./gradlew clean build
+      - run:
+          name: Download Dependencies
+          command: ./gradlew androidDependencies
+      - save_cache:
+          paths:
+            - ~/.gradle
+          key: jars-{{ checksum "build.gradle" }}-{{ checksum  "app/build.gradle" }}
+      - run:
+          name: Run Tests
+          command: ./gradlew lint test
+      - store_artifacts:
+          path: app/build/reports
+          destination: reports
+      - store_test_results:
+          path: app/build/test-results
+# See https://circleci.com/docs/2.0/deployment-integrations/ for deploy examples