Add NegatedQuery for Mapper#reject
Use SQLValue to serialize ints and floats
Move value wrappers out of serializer namespace
Explicitly require JSONHash
Extract as much serialization as possible

I'm really happy for you, Serializer, and imma let you finish, but
SQLValue has the best value serialization of all time! OF ALL TIME!
Serialize JSON hashes with boolean values
Correct spelling error
Add the ability to update records
Fix SQL-injection protection for strings

Postgres uses two single quotes to escape a TEXT value rather than the
\' combo.
Add #map and #any? to Postgres::SerializedData

Ideally, it should be fully Enumerable-compliant. Maybe later.