Scripts/GruulsLair: reworked InstanceScript

Known Issue: position desynch after creature respawn
Merge branch 'master' of github.com:TrinityCore/TrinityCore
[DB/SAI] Vile Like Fire!

Fixes #6524
[DB/SAI]: I've Got a Flying Machine! (11390)

Fixes #6609
Script/Ahnkahet: Fix warning
[DB/Errors] Fix a few DB errors.
Scripts/Halls of Reflection: Fixed accessing uninitialized memory
[DB/Errors] Really fix a few more errors.
Tools: Fix compiler warnings
Scripts: Fix two issues found by Valgrind

==3400== Invalid write of size 8
==3400==    at 0x1241C32: instance_ahnkahet::GetInstanceScript(InstanceMap*) const (instance_ahnkahet.cpp:54)
...
==3400== Conditional jump or move depends on uninitialised value(s)
==3400==    at 0xB5DEAE: std::tr1::_Hashtable<unsigned long, std::pair<unsigned long const, Creature*>, std::allocator<std::pair<unsigned long const, Creature*> >, std::_Select1st<std::pair<unsigned long const, Creature*> >, std::equal_to<unsigned long>, std::tr1::hash<unsigned long>, std::tr1::__detail::_Mod_range_hashing, std::tr1::__detail::_Default_ranged_hash, std::tr1::__detail::_Prime_rehash_policy, false, false, true>::_M_find_node(std::tr1::__detail::_Hash_node<std::pair<unsigned long const, Creature*>, false>*, unsigned long const&, unsigned long) const (hashtable.h:830)
==3400==    by 0xBDA4CA: std::tr1::_Hashtable<unsigned long, std::pair<unsigned long const, Creature*>, std::allocator<std::pair<unsigned long const, Creature*> >, std::_Select1st<std::pair<unsigned long const, Creature*> >, std::equal_to<unsigned long>, std::tr1::hash<unsigned long>, std::tr1::__detail::_Mod_range_hashing, std::tr1::__detail::_Default_ranged_hash, std::tr1::__detail::_Prime_rehash_policy, false, false, true>::find(unsigned long const&) (hashtable.h:698)
==3400==    by 0xBDA5BF: HashMapHolder<Creature>::Find(unsigned long) (ObjectAccessor.h:67)
==3400==    by 0xCB5C03: Map::GetCreature(unsigned long) (ObjectAccessor.h:114)
==3400==    by 0xB6E6EF: Unit::GetCreature(WorldObject&, unsigned long) (Unit.cpp:13023)
==3400==    by 0x10F0790: boss_hydross_the_unstable::boss_hydross_the_unstableAI::Reset() (boss_hydross_the_unstable.cpp:164)
Merge pull request #10559 from Discover-/Taxi-Benchmarking

Core/Misc: Implement CMSG_SET_TAXI_BENCHMARK_MODE to toggle PLAYER_FLAGS...
Core/Settings: Fix a crash if worldserver.conf DataDir setting is empty
[DB/SAI] Sleeping Giants (11432 & 11433)
Core/Settings: Fix build in non cpp11 compilers

std::string back() was only introduced in C++11, a pity..
DB/Conditions: Awakening Rod
Fix uninitialized UpdateMask field

Initialized UpdateMask::_bits to NULL in all constructors.
UpdateMask(UpdateMask const& right) constructor sets the field count with SetCount() method before any field initialization. This means that SetCount() will call delete[] on the uninitialized _bits pointer field, leading to undefined behavior.
DB/SAI: The Last of Her Kind credit update

By @untaught, fixes #10254
Merge pull request #10617 from jackpoz/updatemask_fix

Fix uninitialized UpdateMask field
DB/SAI: Cannot Reproduce (13320,13355) & Retest Now (13321,13322,13356,13357)
Core&Tools: Fix multiple issues found by a static code coverage tool