bll: remove usage of RandomUtils

RandomUtils is a wrapper to non secure random of java that is not used
nor required within runtime.

implementation of random utils is way too complex than required and
provided as a wrapper instead of utility.

move class to tests.

Change-Id: Id20da6d8eb93ebbd237d20705440c5e583fc486e
Signed-off-by: Alon Bar-Lev <alonbl@redhat.com>