- Emit BOOL rather than BOOLEAN for MySQL booleans in DDL, for old versions

- Emit BOOL rather than BOOLEAN for MySQL booleans in DDL, for old versions
  of MySQL (#583)
- MySQL columns (such as times) with colons in their default values couldn't
  be roundtripped, fixed  (also in Postgres, but not fixed here.)
- BINARY/VARBINARY columns aren't really binary at all on ancient versions
  of MySQL.  The type.Binary(123) passthrough now always makes BLOBs.
  Removed the short-lived MSBaseBinary.
- Added mysql.get_version_info, given a connectable returns a tuple of server
  version info.
- Backed off on the reflection tests for older versions of MySQL, for now.