To make libDAI-0.2 compatible with Visual C++:

clock_t -> long
Bla::max() -> maxBla()

in some files:
#include <xmath.h>
#include <float.h>

isnan() -> _isnan()

in lc.h: implemented belief(const VarSet &ns)

in mr.cpp: #include <boost/math/special_functions/atanh.hpp>

in mr.cpp: implemented MR::belief(const VarSet &ns)

in mr.h: double init_cor() -> void init_cor()
         implemented MR* clone()

in util.cpp: changed toc()

in varset.h: class VarSet : private std::set<Var> -> class VarSet : public std::set<Var>




The current SVN snapshot uses several GNU CC extensions 
(for exceptions, not so important, and for enums, which gives more portability problems)
