Include generated source files in sources JAR deployed to Maven Central

[Marcono1234]

trafficstars

Relates to #94

Would it be possible to include the source files generated from the src/build/source_templates files in the ...-sources.jar deployed to Maven Central?

That would allow to debug through the code in the IDE, and would also make it easier for users to understand the implementation.

Current workaround: Build the project locally, then combine the source files from /src/java, /src/java-unsafe and /build/java in one directory. And configure your IDE to load the source files for lz4-java from that directory.