Improve math module (#396)

* Improve math module

- Mark almost everything constexpr
- Equality (a == b) is now exact, down to the bit level. If you want approximate equality use the new ApproxEqual method/static method
- Rename Nz::Extend to Nz::Extent
- Removed Make[] and Set[] methods in favor of their static counterpart and operator=

src/Nazara/Utility/SubMesh.cpp

@@ -30,7 +30,7 @@ namespace Nz
 			return;
 
 		for (UInt32 i = 0; i < vertexCount; ++i)
-			normals[i].MakeZero();
+			normals[i] = Vector3f::Zero();
 
 		TriangleIterator iterator(*this);
 		do
@@ -66,8 +66,8 @@ namespace Nz
 
 		for (UInt32 i = 0; i < vertexCount; ++i)
 		{
-			normals[i].MakeZero();
-			tangents[i].MakeZero();
+			normals[i] = Vector3f::Zero();
+			tangents[i] = Vector3f::Zero();
 		}
 
 		TriangleIterator iterator(*this);