Fix Javadoc and reenable maven-javadoc-plugin failOnError

[rizwantanoli]

Made fixes pertaining to #1

[iroskam]

Despite whole files being marked as changed I only see the removal of some Javadoc return annotations. It is beneficial to have the return types stated in the Javadoc.

Did you change line endings? What other reason would git mark the whole file as changed?

[sappenin]

Hi @rizwantanoli This project is currently dormant. All future work should probably happen in the Hyperledger Quilt project, although we don't yet have much around an ILP Connector.

I'm working on something in my own repo (https://github.com/sappenin/java-ilpv4-connector) if you want to follow along, but it's not yet ready for primetime. Once I get things a bit more stable, I'm hoping to push out an LPI Plugin project (follow that here: https://github.com/sappenin/java-ilp-plugin), as well as implementation of Routing and other ILP RFCs related to a Connector. Stay-tuned.