Remove all compilation warnings reported by Eclipse

There is a lot of compiler warnings reported in Eclipse - in order to avoid overlooking new warnings indicating sub-quality code, we need to get rid of those currently present so the IDE reports no errors, warnings or other compilation information. (This may also need to be done for IntelliJ).

Most of the warnings are due to pre-Java5 code not being either generified or having the warnings suppressed. The proper approach is to introduce generics on the classes.