Allow configuring default database name
https://discuss.tryton.org/t/sao-not-showing-database/2405/18 showed that some user may not have access to template1. So we should allow to customize the default name.
https://discuss.tryton.org/t/sao-not-showing-database/2405/18 showed that some user may not have access to template1. So we should allow to customize the default name.