Core/Chat: Fix assert triggered by .npc add

Fix an assert in Aura::_UnapplyForTarget() caused by ".npc add" changing the guid of the spawned Creature.
Scripts/Misc: Fix uninitialized values

Fix uninitialized values in scripts reported by valgrind.
Fix target and GetOwner() NULL dereferences .
Updated the compilation requirements to compile the core.

For more informations read the following thread: http://www.trinitycore.org/f/topic/9214-updated-trinitycore-requirements-deprecation-of-old-compilers/
DB/Classlevelstats: Add base damage for exp2
DB/Classlevelstats: Base damage for expansion 1
DB/ClassLevelStats: All stats for testing.
Core/Transports: Fix array overflow

Fix an array overflow in TransportMgr::GeneratePath() spline code.

Valgrind log:
 Invalid read of size 4
  at : G3D::Vector3::operator*(float) const (Vector3.h:650)
  by : Movement::C_Evaluate(G3D::Vector3 const*, float, G3D::Matrix4 const&, G3D::Vector3&) (Spline.cpp:103)
  by : Movement::SplineBase::SegLengthCatmullRom(int) const (Spline.cpp:171)
  by : Movement::SplineBase::SegLength(int) const (in /home/jackpoz/trinity/bin/worldserver)
  by : Movement::Spline<double>::initLengths() (SplineImpl.h:86)
  by : TransportMgr::GeneratePath(GameObjectTemplate const*, TransportTemplate*) (TransportMgr.cpp:125)
  by : TransportMgr::LoadTransportTemplates() (TransportMgr.cpp:78)
 Address 0x1d07d154  is 8 bytes after a block of size 300 alloc'd
Buildsystem: Fix GCC not being recognized on Ubuntu

Fix CMake not recognizing /usr/bin/cc as GCC on Ubuntu ( 13.10 x64 ) .