FIX minor bug in MySQLRetrieveUser which would not return the user name

src/main/java/org/caosdb/server/database/backend/implementation/MySQL/MySQLRetrieveUser.java

@@ -81,6 +81,8 @@ public class MySQLRetrieveUser extends MySQLTransaction implements RetrieveUserI
         while (roles_rs.next()) {
           if (ret == null) {
             ret = new ProtoUser();
+            ret.realm = principal.getRealm();
+            ret.name = principal.getUsername();
           }
           if (ret.roles == null) {
             ret.roles = new HashSet<String>();