New in 5.18.5 - April 2015

* Guile 1.6 is now obsolete.  1.7/8 or newer from now on.
  Fixed issues with Guile managed locale string processing.
  (It keeps getting better and better all the time and I
  must keep adjusting over and over all the time.)
* more Guile-config somersaults
  config/misc.def: sometimes, "pkg-config --cflags-only-I" yields
  multiple directories for Guile and that incantation is the only
  way to find libguile/version.h and that header is the only way
  to determine the micro version and the micro version is the best
  way to check for certain types of breakage.  (Testing is too
  convoluted.)
* for-each handler functions may now be able to free (or not)
  the file text via the "handler-frees" attribute.

New in 5.18.4 August 2014

* Do Not Edit (dne) warning:  the default of printing a date in the
  warning has now changed to not doing so.  The "-d" option to
  suppress the date is now deprecated (ignored).  A new option, "-D"
  will cause the date to be included.  The environment variable,
  "AUTOGEN_DNE_DATE" overrides everything.
* The RETURN function was not completely implemented and only
  partially worked.  It is working now.

New in 5.18.3 May 2014

* Auto-edit Guile headers that depend upon configure values
  most especially:  noreturn
  but check for "ptrdiff_t" in our configure too, so that Guile does
  not create its own duplicate definition.
