Merge branch 'master' of github.com:RoboCupDev/tournamenter
Implemented restoring the DB from a JSON file.

- Added --restore option to the command line
- The process at first deletes everything from the current models and
  then creates all their contents from scratch (actually that JSON file)
A few comments
Merge pull request #20 from RoboCupDev/load-backup

Load backup