Correction of mathematical functions.

BoundingVolume: Add of constructor and setter OrientedBox. Extend is now
up to date.
Box: Use of <T>. Return this
Frustrum: Use of <T>
Matrix: Use of <T>
OrientedBox: m_corners is up to date
Rect: Add of operators /= and /. Return this
Sphere: Add of Intersect and Contains with box. Little corrections.
Vector2: Return

TaskSchedulerImpl: Add of include header cstdlib to compile because of
std::div
HardwareInfo/main: use of accentAigu
Merge branch 'master' of https://github.com/Gawaboumga/NazaraEngine into Gawaboumga-master
Fixed some of the pull request code in order to merge it
Merge branch 'Gawaboumga-master'