Fix issue 8 regarding nondeterministic code generation for quadrature optimisations.
Minor fix in unit tests to reflect update in the way symbols are created.
Fix another bug related to new interface of the create_symbol function for quadrature optimisation.
Update reference data pointer to ba78b34c89595068ac6cfa7f98ee5f1990b0ef97.
Merge branch 'k.b.oelgaard/fix-merges'