Made Potential::PrintHeader() virtual to add diferent headers to diferent classes. Added RanGen::getseed(). Potential is no longer friend of RanGen class (relation obsolete). PrintHeader()'s from xSM2 and TwoHDM classes now print the simplified field equation, they also only show the ranges of variables that actually have checked ranges (not showing the dependent ones unless the input file sets a range for them). TwoHDM also shows the ranges for alpha and tanbeta.