Open code coverage

closes #15,#16

.travis.yml

@@ -17,6 +17,7 @@ before_install:
   - if [ "$TRAVIS_OS_NAME" == "linux" ]; then jdk_switcher use "$CUSTOM_JDK"; fi
 
 script:
-  - travis_retry mvn clean install
+  - travis_retry mvn -B clean apache-rat:check
+  - travis_retry mvn -B clean install cobertura:cobertura
 after_success:
-  - bash <(curl -s https://codecov.io/bash) -t 11a6acce-59a1-4586-9bf6-164878d045cf || echo 'Codecov failed to upload'
+  - bash <(curl -s https://codecov.io/bash) -t 225f1740-55fa-437e-a378-16b70031f728 || echo 'Codecov failed to upload'