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.

2015/endoh4/prog.orig.c

@@ -0,0 +1 @@
+f(y,x){int m,z;for(m=z=1;m*m<=y?z=y%m?z:m:x+1?z<2?x?f(x,0):putchar(64):f(z,x),putchar(x?10:32),y-=z:(f(z,y/z),0);)m++;}main(y){f(y-1,-1);}