bool_and and bool_or aggregations
QueryRunner instances for UUID
Merge pull request #62 from silkapp/queryrunner-uuid

QueryRunner instances for UUID
Merge pull request #63 from silkapp/bool-aggregations

bool_and and bool_or aggregations
Implement orderBy.
Unpackspec pc boilerplate
ExprArr: add Num instance.

Makes writing where/restrict expressions much nicer.
cast
Dubious QueryRunner instance for nested Maybes