Gracefully handle existing default login roles If multiple databases are created in the same PostgreSQL cluster, existing roles are now properly re-used. This also fixes running database tests on a cluster that already has these roles, which was broken since rev. 5e38667f740c, because it silently fixed a test for existance of roles that failed if proper creation of the role 'sysadmin' failed during setup of the test database.

# Development

## Backend

You need a working [Go](https://golang.org/dl) build environment (1.10+).

* Install dependencies

    `sh 3rdpartylibs`

* Build

    Prerequesite: compile server
    ```
    cd cmd/gemma/
    go build
    cd ../../
    ```

* Run
    Run server with  `./cmd/gemma/gemma`

## Client

See [client/README](../client/README.md) for details.