JDO - basic structure

Today, i made a basic structure of database in JDO. For begin i implemented just simple structure, for that what we need. It must be extended if we will want to add more applications. But for testing functions is better to have simple database.

I haven't implemented parts from model which supports more applications, like challenge relationship to program, user groups. At this moment user can only be a part of one university. Users cant create their own groups. In the JDO are only simple methods for adding universities and cities, and states to database. Of course there are methods for listing of data saved in the database.