MSVC:  inline functions that use static members are moved into *.cpp files to avoid undefined symbols

MSVC: switch to boost::time instead of linux time, RootMinimizers now compiled as static, switch to MathFunctions::isnan in functional tests

First version of chapter "Fitting" of the manual, correction of typo in IMinimizer.h and modification of PrintResults in FitSuite.cpp

- 3rd person form: "Does" this or that.
- For all const methods that return something: "Returns" ...
- For boolean return value: "Returns true if " ...