Bumping Apache POI library. A new one just came out with 'significant performance improvements and bug fixes'.
Upping barbecue version to one I can actually find in Maven repos...
Adding a 3-deep sub-report for the purpose of demonstrating the sub-sub-report CustomExpression bug:

Unknown property 'customExpression_for_DJR_1200_COLUMN_2'

(See line 134)
Augmenting 3-deep report for the purpose of demonstrating the sub-sub-report CustomExpression bug:

Unknown property 'customExpression_for_DJR_1234_COLUMN_0'

(See line 130)