Javadoc Re-add and DDM Template update

Besides the re-add, I also included changes dealing with [LPS-45107](https://issues.liferay.com/browse/LPS-45107), which was documented as one of our [breaking changes](https://github.com/liferay/liferay-portal/blob/master/readme/7.0/BREAKING_CHANGES.markdown) for 7.0. Thanks!

https://issues.liferay.com/browse/LRDOCS-987