Doxygen comments.

Formfactors: integrand of imaginary part is real.

Transform reduced to 3x3 rotation.

Tried removal of Rotate from Geometry which however is required by IsGISAXS07.
Will be reverted in a minuted.

  (typedef Geometry::BasicVector3D<int> IndexVector3D
   now in ISelectionRule.h).
Class description for SimpleSelectionRule.

Forbid shorthand a*b, request a.dot(b) or dotProduct(a,b).
Remove "virtual" from ~BasicVector3D.
Provide templated implementation for almost all methods,
  resolving issue #237.

Repair Python compilation by restoring default constructor in HomogeneousMaterial.h

Standard doxygen comments

more work on class and method comments

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>