Domain documentation

- Domain classes diagram (available at https://www.draw.io/?#G0ByyXLa89xHUdTEl0MktFWnk2LUE).
- Itroduction to system domain design.
- Explanations for specific domain sections of the application:
    - Job searches
    - MyMenu
    - Employees
    - Applicants
    - Vacation reports
Merge pull request #336 from AlphaGit/domain-documentation

Domain documentation
Project memories: JD

- Personal experience in software development
- Advantages and disadvantages present at start of the project
- Challenges found once the project actually started
- What decisions were made and how, how did they affect the project
- My place in the team, my skills provided
- Problems found and how were those approached
- What was learnt from the project, technically and personally
- What can be said about the project ending