Core/Spells: Implement Periodic mechanics

Change behaviour of single target periodic aura ticks to be more blizzlike
Also add some missing handling of SPELL_AURA_MOD_CREATURE_AOE_DAMAGE_AVOIDANCE
Fixes Deep wounds and Chimera Shot Serpent
Remove an ancient hack with Drain Soul, spell id 100001 can now be deleted from spell_dbc table
Allows Rolling dot mechanics and allows DK's to roll diseases with pestilence,
see link for info:

http://forums.elitistjerks.com/topic/82503-frost-dps-in-333this-will-be-a-day-long-remembered/page-88
DB/Conditions: Fix conditions for Xink gossip
DB/GameObjects: Fixed some phasing of certain gameobjects in Northrend and DK's area
DB/GameObjects: Fixed the phasing of the remaining flags in WinterGrasp
DB/GameObjects: Deleted no longer needed gameobjects spawns since their phaseMask correction
Script: Minor optimization in spell_unlocking_zuluheds_chains
Revert "Core/Calendar: Fix memory leak when malformed CMSG_CALENDAR_ADD_EVENT is received"

This partially reverts commit 51e38872c72e16bb0f09e660c2660759021b2176.
The stack-initialized variable calendarEvent would have called CalendarMgr::FreeEventId() when it went out of scope, marking the current event id as free and allowing next event to overwrite current event.
This doesn't fix the memory leak issue which still needs to be addressed in a proper way.
Core/Calendar: Sanitize calendar event parameters

Prevent events added in the past which in some conditions would cause an infinite loop in the client.
Merge pull request #12228 from Unholychick/patch_periodics

Core/Spells: Implement Periodic mechanics
Fix Warnings
Merge pull request #12240 from Unholychick/patch-3

Core/Build: Fix Warnings
Core/Handlers: Move a couple of logs to debug, they can appear without anything abnormal due to client latency