Spell optimizer correctly
Handle null joinConditions

If there are no conditions, it's often null. This doesn't always
mean it's a cross product, just that we're considering the cross
product
Added a rulesTest for NullPointerException
merge ScottDugas: Hibernate tests causing null pointer exception

Merge pull request #1439 from ScottDugas/sql-layer/hibernate-null-pointer
https://github.com/FoundationDB/sql-layer/pull/1439