restore *.orig.c to each entry

Under each yyyy/dir there is a file of the form '*.orig.c'
containing the original source code, or as close as we can
get to the original source code.

1993/plummer/plummer.orig.c

@@ -0,0 +1 @@
+char*_,*O;main(S,l)char**l;{*(O=*(l+++S-1)-1)=13,*l[1]=0;for(;;)for(printf(*l),_=O-1;_>=*l&&++*_>(S+*O+S)*S;*_--=(S+*O)*S);}