Fix most aspects of focus damage spells (#245)
* Make GameServer usable in tests
* Add RampingDamageFocus for Heretics
This replaces HereticDamageLostOnPulse and HereticDamageSpeedDecreaseLOP
Changes:
- no double ticks
- snare doesn't give immunity
- damage increase is now linear
- damage calculation now taken from DD
- damage caps at given damage increase percentage
- uninterruptible flag makes focus ruptible only within 200 range (spell
cast completely uninterruptible for now)
- caster is able to switch target without breaking focus (focus not
following)
* Fix DelveInfo for RampingDamageFocus
