Remove lombok

[sothawo]

We already removed lombok from the production code. Now we see problems when trying to build the library with JDK16:

java: java.lang.IllegalAccessError: class lombok.javac.apt.LombokProcessor (in unnamed module @0x39054474) cannot access class com.sun.tools.javac.processing.JavacProcessingEnvironment (in module jdk.compiler) because module jdk.compiler does not export com.sun.tools.javac.processing to unnamed module @0x39054474

We use lombok only in test code and only for generating getter/setter and constructors - nothing that any decent IDE could not generate as code as well. By removing lombok we will need to add some more boilerplate code to test entity classes, but we get rid of these JDK internal accessibility problems.