CDK-581: Updates for java8

This PR alters the travis config to test java8 without pushing to master. This will not be part of the commit when merged.
Java 8 requires an updated findbugs, which caught that this reader doesn't implement the `Iterator` API properly. Iterators should not advance on calls to `hasNext` and must throw `NoSuchElementException` in next if there is no next element and `hasNext` would have returned false.