DateTimeInterval arithmetic and comparison; DateTimeDuration and DateTimeInterval conversions to string.
Fixed a typo that would cause reflection on BelongsTo<...> to fail.
Fixed ColumnAbilities LiteralOrderingAbilities. Added missing include for maybe.
Made persistence::relational_algebra::literal extensible.
DateTime: Preliminary timezone support.
persistence: DateTime bindings.
Fixed some bugs in persistence::Projection.
Updated blog example.
Updated TODO