Modified call to cmd_proc.c

 * Simplified cmd_proc() call so it does not return a VIC structure
 * Removed unused variables from cmd_proc()
 * Changed order of cmd_proc() and in initialize_global() in vic_classic()
Moved force_type_struct and param_set_struct to vic_driver_classic.h
Cleanup: removed files that were part of the defunct dist_prec part