DB/Gameobject: Allow to target 2 gameobjects

Closes  #13093, closes #13094
Core/Misc: Added const modifier to MessageBuffer::Write parameter
Core/WorldSocket: Refactored client packet header check
DB/Quest: The Demoniac Scryer

Closes # 2610

Script for http://www.wowhead.com/quest=10838/the-demoniac-scryer
Core/Misc: Refactor scripts to fix static analysis warnings

Fifth batch of fixes targeting 100 issues reported by Coverity
Core/Scripts: Nuke db_script_string table and make SCRIPT_COMMAND_TALK with broadcast_text instead

Original code by @Ascathor with modifications
Closes #13092
SQL: Update /dev/world_database.sql

Forgotten change of 27479cf571cf65c9e1657e9c465974449173dc3f
DB/Misc: Fix visual appearance for some quest flight paths

Fix appearance of player when taking flight for As the Crow Flies and Spiritual Insight

Link the spells which give transform (Stormcrow Shape for As the Crow Flies and Spiritual Insight for Spiritual Insight

Script to remove this at end of path, the zangarmarsh one lasts about 5 seconds longer than flight path, but the dragonblight one has 1 min left at end so needed to remove that,

Also dont know if anyone can think of a way of how to this but during as the crow flies the player is meant to receive a few whispers from ysiel during the flight path,

If you search spell_dbc for as the crow flies you will find there are a number of auras with name as the crow flies whisper aura with different effect msic values and different durations ranging from 3 to 467 I have a feeling these are meant to trigger the whispers when the auras expire think the values in effectvaluemisc2 maybe event ids.
Merge pull request #1 from TrinityCore/master

Update local branch from TC master