hamilton class rewritten
numerical and analytical version are subclasses now. Choosen by
parameter in config file and implemented by a virtual function.
Furthermore is the range of the parameters in the config file.
factor of 2 corrected (not divided by number of particles anymore)
loop and status slightly updated (adding a 0.000001*stepsize factor to
solve roundoff problems.)
output file is now also an option in the config file.