Added Moved Warlocks' Grimoire of Sacrifice to its own file and properly handle it.

E.g. do not try to use it without any pet or if the player already have the aura.
Fixed Soul Link.

Support talent changes.
Do not suggest it while Grimoire of Sacrifice is active.
Fixed Warlocks' pet summoning quirks.

Do not suggest to summon a demon while Grimoire of Sacrifice is active.
Use IsMounted() instead of home-brew IsMountSummoned().