Protect-time changes

Protect-time has gained some positive changes.
The invulnerability time is still 5 seconds.
Invulnerability is canceled earlier than this time if:
- run away from the spawn point by one meter.
This is more true in relation to other players, and allowed to add dynamics to the gameplay.
We added a visual protection indicator in the form of a shield in the lower left corner of the screen. Also, the indicator is displayed above other players on the map.
