[JBRULES-2936] replace jexcelapi with apache poi
[DROOLS-71] Prevent NPE when there is a null value in a list used by a from element
(cherry picked from commit 3c66d62270d343a573748d1d5850ca2054e99917)
[DROOLS-73] avoid infinite loop during DSL expansion
(cherry picked from commit 3a2082c7e3be099b5a481878ddb1ccc3f5c9bae6)
DROOLS-25: merging patch and enforcing preload
(cherry picked from commit 03abd1c5a57b82d7420af74a4b3c0bbd17423ac0)