Issue 653 - added support for DateTimeOffset properties in Redis.
Also added tests for all built-in data types for all providers except
Azure - which needs special treatment (PartitionKeys etc).
As noted several of the data types are not yet supported on all providers
- so these have been moved to a Supplemental set of tests which are
  implemented only on the providers that support them. As SQL Server and
  SQLite start supporting these we should move those data types into the
  BuiltInDataTypes* classes and remove them from the Supplemental
  ones.