Enable support for utf8 for database
Enable support for utf8 for database

This fix adresses the problem described in
https://github.com/quarkslab/irma-frontend/pull/36. This fix must be applied
with the related fix on the frontend.

hirokihamasaki/irma,hirokihamasaki/irma,quarkslab/irma,quarkslab/irma,hirokihamasaki/irma,quarkslab/irma,hirokihamasaki/irma,quarkslab/irma,hirokihamasaki/irma