Create abstract hideable dictionary class
Refactor theme entity class to inherit from hidable dictionary
Fix a typo in class name not corresponding to file name
Add getCount method to hidable dictionary class
Refactor exercise entity to inherit from hidable dictionary
Fix a typo in parent class name
Move title attribute to parent class
Fix typos: primary key is not necessarily named "id"
Merge pull request #148 from ob-ivan/decopypasteEntities

Decopypaste entities