ISPN-4528 Genericize remaining M/R internal classes

Master only. See https://issues.jboss.org/browse/ISPN-4528 for more details. 
Vladimir, what error are you seeing? Which Java version? I just removed the `@SuppressWarnings` annotations and it compiled fine for me, without any changes, both with Oracle's Java 8 and OpenJDK 1.7.