added provenance to table in fromPairTables
removed serialize operator and freeze from operators
removed disconnected table from operators
added setProv to base tables
fast paths in pairtable
started toSQL implementation
fixed bugs when executed in partitionedtable
added complete flag
added support for complete cross product in buildht
added partitioned table
added complet flag
removed freeze tests, added partitiondtable tests
fixed bug in table.groupby.  forgot to pass alias into partition() call
fixed colidx bug in normalize mappings when rowschema col order doesn't match table schema col order
tests for partitionedtable impl pass