No error code in database_exception

[michihenning]

When I get a database_exception, I can get at the string for the error message, but not at the underlying error code. That's really inconvenient because I can't selectively react to different error conditions other than by parsing the error string. Doing that is really brittle. It would be nice to have an accessor on the exception classes that returns the underlying error code.

[vinzenz]

A pretty good point, I will add something to make this possible.

[michihenning]

Thanks for the very quick fix!