Removed instance() from python functional tests; ISingleton and MaterialManager are (probably) thread safe now

Emptied Coordinate3D.h:
   only use typedef Geometry::BasicVector3D<int> IndexVector3D;

Outcomment Python compilation.
Work on layout while studying code.

to replace Coordinate3D<int>

(was mathematically incorrect).
Change order of compilation: basics first.

Renounce use of delegating constructors to avoid warnings from pre-C++11.
Improve comments.

Removed duplicate function names (rho, r) from BasicVector3D.

Conflicts:
	Core/Fitting/src/FitSuite.cpp

Conflicts:
	Core/mainpage.dox