SPARKC-312: Implementing FilterOptimizer

[ponkin]

FilterOptimizer will to transform where clause to equivalent disjunction normal form. For example where clause a = 5 and (b > 5 or b < 3) can be transformed to equivalent a = 5 and b > 5 or a =5 and b < 3, so now we can create two different table scans with where clause a = 5 and b > 5 and a =5 andb < 3 and union them.