Eclipse RDF4J 4.0.0

RDF4J 4.0 is a major new release, with the following highlights:

• upgrade to Java 11 as the mimimal required Java version
• compatibility with Java 16
• removal of several long-deprecated components and public interfaces
• reorganization of the modular structure for greater flexibility
• the introduction of new Spring components to make using RDF4J in combination with the Spring framework easier
• a massive number of smaller fixes and improvements