Core/Spells: Fixed Shadowstep taking the caster out of combat while it shouldn't
Core/Players: Fix haste rating formulas. They're supposed to be the addition, not the multiplication of all available bonuses

- This change matches client formulas
Core/CreatureAI: Implement CreatureAI::TalkToMap for all your map-wide talking needs. Could also replace Battleground::SendChatMessage
Core/Spells: Fix Cheat Death formula
Core/Players: Update the player's zone and area after update the player's
position server side.
Merge pull request #12171 from Ankso/player_update_zone

Core/Players: Update the player's zone and area only after the player's position is updated server-side.
Martek the Exiled's prerequisite quests

Fix by @untaught
Core/RBAC: fix RBAC_PERM_COMMANDS_BE_ASSIGNED_TICKET and RBAC_PERM_LOG_GM_TRADE permissions
Core/NetworkIO: Fix performance loss when handling bad packets

Revert f9cb4280bd8f1c29e4acbae5339bce40c3b52bcb which retrieved the callstack each time a ByteBufferPositionException or a ByteBufferSourceException occurred, for example with bad packet structure.
Core/QuestPOI: Mitigate possible DoS with CMSG_QUEST_POI_QUERY

Avoid sending POIs for same quest if the client somehow sent duplicates quest id in same CMSG_QUEST_POI_QUERY packet. This also reduce the effects of possible DoS and increases the difficulty to cause it.
Fix a typo which caused no quest POIs to be sent at all if the client queried data for 25 quests.
Core/Misc: Code cleanup

Remove old unused opcode handler WorldSession::HandlePageQuerySkippedOpcode() for CMSG_PAGE_TEXT_QUERY since it's already handled by WorldSession::HandlePageTextQueryOpcode()
Core/Misc: Added utility method for checking is two sorted containers have a common element
Scripts: Remove unused variables (kept as comment)
Script/Shadowmoon Valley: Remove hack in npc_shadowmoon_tuber_node.

This script will be converted to SAI (if possible) later.
Core/Spells: Implement SPELL_ATTR4_FIXED_DAMAGE

Spells with this attribute will ignore damage taken auras except for mechanic damage taken (trauma, etc) and will ignore resilience because the damage caused by those spells is based off another spell' damage
Core/Misc: Kick player in case of multiple CMSG_PLAYER_LOGIN

Kick player in addition to logging an error in case of multiple CMSG_PLAYER_LOGIN.
Merge pull request #12032 from Trisjdc/haste_formula

Core/Players: Fix haste rating formulas
Merge pull request #12182 from Xter/rbac

Core/RBAC: fix RBAC_PERM_COMMANDS_BE_ASSIGNED_TICKET and RBAC_PERM_LOG_G...
Core/Util: A couple useful new functions for EventMap, as well as getting rid of some old junk
Merge pull request #12135 from Trisjdc/event_map_extension

Core/Util: A couple useful new functions for EventMap