Workaround for non-standard include file in r.le

I don't know whether this will be useful to anyone else, but I did figure
out how to get around needing the "opendir" and "closedir" functions to
open a directory stream. These functions are defined in the "dirent.h"
file in SunOS, but in the "dir.h" include file on other systems. The
workaround was to copy the code out of dirent.h that defines a DIR
structure and the code that declares the opendir and closedir functions.
This code is only about 8 lines. I simply put it in the central include
file for the r.le programs, thus no need to use "#include dirent.h" or
#include dir.h. Crude, but straightforward.

  Bill Baker
  bakerwl@corral.uwyo.edu