Support postgres type: tstzrange

[jh-RLI]

I have tried to create a table using oem2orm. The table contains a column with the postgres-type tstzrange. It seems to me that the data type is not supported by the oedialect.

SQLAlchemy version:
sqlachemy: 1.3.16

Using this type:
from sqlalchemy.dialects.postgresql import TSTZRANGE

The exception I get back when creating tables (using sqlalchemy):
ConnectionException: HTTP 400 (Bad Request): Unknown type (tstzrange).