default Optional<String> getConnectionUrl() {
        return getAsString(DbmsUtil.CONNECTION_URL);
    }
Returns the explicit connection URL to use for this {@code Dbms} if the
user has specified one, or an empty {@code Optional} if one should be
generated automatically by the {@code DbmsType}.

@return  the explicit connection URL to use for this {@code Dbms}
runtime-parent/runtime-config/src/main/java/com/speedment/runtime/config/Dbms.java