[THS] Basic lands of Theros.
Refactored AttacksAttachedTriggeredAbility, added SacrificeSourceTriggeredAbility.
Added AddCounterAttachedEffect.
Fixed a bug that triggred abilities of permanents that were controlled by a player that is not the owner could sometime trigger for a wrong player (Fixes #271).
Added AttachedToCounterCondition and some minor changes.
[THS] Added 17 cards.