Extend grouping set limits from int to long

Grouping sets is broken for >32 columns because of usage of Int for bitmap (also GROUPING_ID virtual column). This assumption breaks grouping sets/rollups/cube when number of participating aggregation columns is >32. The easier fix would be extend it to Long for now. The correct fix would be to use BitSets everywhere but that would require GROUPINGID column type to binary which will make predicates on GROUPING_ID difficult to deal with.