Made interference function strategies independent of scalar/matrix formalism; this now enables all strategies to be used with polarization

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

Insert new header comment block, remove old one, manually improve file comments (defines / implements), change brief function description to doxygen format, remove some outcommented code

Complex integrator implemented; standard integrator now reuses integration workspace, FormFactorSphere refactored

Fixed bug in InterferenceFunction2DParaCrystal; fixed warnings about size_t -> int conversions; updated Xcode project file

Fixed issues with complex Bessel function in cylinder form factor + corrected normalization of Gaussian and Lorentzian form factors

Evaluate form factors for complex wave vectors (1): provide interface and implemented it for part of the Formfactors