water/drowning - Restore health lost by drowning fully after leaving waterlevel 3

[Chrissstrahl]

Health is not yet restored fully after emerging out of the water.
Damage(substraced health) that is given to player while under water by drowning should be restored to health again.
The primary goal is to keep compatibility and NOT to add any new variables to Player class.

Related variables and functions:
void Player::WorldEffects( void )
player->air_finished
player->drown_damage
player->health
player->waterlevel