Added lines to FindPGPLOT that make it easier on szstems with pgplot in
/usr/local/pgplot
Some MPI systems seem to retrun no error upon init, even if diffev was NOT started with mpiexe or mpihydra. Only one processor is returned, I use that to turn MPI off.
Source Code Cosmetics, Placed all remaining files into MODULEs. Exception are err_appl.fio kdo.f90 and upd_par.f90, as these to cross references with lib_f90.
The required to take out several routines into new files to avoid circular references between modules.
Added proper definitions of dummy parameters, with INTENT and all
Added INTERFACE blocks to routines in err_appl.f90, kdo.f90 and upd_par.f90 to reduce likelihood of code errors