Merge pull request #2 from mboron/master

Initial version of data model
Merge branch 'master' of https://github.com/Door43/OBS-Translation-App
Merge pull request #3 from mboron/master

ITranslationService and fake implementation to provide some functional example
Merge branch 'master' of https://github.com/Door43/OBS-Translation-App
- Initial version of saving/reading translations from DB.
- Refactoring IPersistenceObject.java: "updated" changed to "modified"
- Refactoring ITranslationNotes.java: set of ITerm replaced by simple String for now.