[Web] URBNG-68 and URBNG-70

Changes include:
- saving and updating the game when switching between steps
- deleting the game (no confirmation dialog before delete, will be fixed soon)
- showing game details (an empty subpage for now) when the game has status 'online' and popping out an alert in other cases (alert will be changed to 'edit the game' view)
- modified game controller, database and angular model to achieve save, delete and update functionality
- changing games' statuses when their start or end time are less than actual date (status is checked when request for the game list appears)