Little corrections

HashDigest: Simultaneous use of int and short
EulerAngles: Use of the macro
Geom: cone was missing
Add of some mathematical functions

Plane: Getters and classic planes
Sphere: Getter
Vector2: Angle between two vectors
Vector3: Same in 3D
New class ray

Class ray who represents a ray in space and who can be used as a line.
Support of classical intersections.
Little fail

Plane: Forgot <T>
Little fail again

Wrong getter
Add of source

Add of the source
UTF8
Obb intersect ray

New method
Suppressions of getters
Added Matrix4::Concatenate static method
Fixed code