Remove unsupported Double primitives

Signed-off-by: Stefan Marr <git@stefan-marr.de>
Fix implementation of #dnu

Signed-off-by: Stefan Marr <git@stefan-marr.de>
Updated core-lib

- some cleanup/optimizations
- added #dnu tests

Signed-off-by: Stefan Marr <git@stefan-marr.de>