mapping drivernames and dropdown values

[edublancas]

we are mapping drivers to know which form to display in the connector widget, however, there are some limitations with the current approach:

• mysql+pymysql map to mariaDB and mySQL. so if a user stores a mariadb connection and then wants to edit it, the dropdown will show up as mysql
• what do we do with unknown drivers? e.g., redshift is stored in the ini file but we don't have a connection template. currently it's showing PostgreSQL (I believe because it's the first template). maybe it'd be better to show a "generic" template? this generic template could show the drivername as a field