Description
int 
jewishtojd ( int month, int day, int year )
     Although this function can handle dates all the way back to the year 1
     (3761 B.C.), such use may not be meaningful.  The Jewish calendar has
     been in use for several thousand years, but in the early days there was
     no formula to determine the start of a month. A new month was started
     when the new moon was first observed.