* configure.in: Added better check for libwrap (the old way failed when

* configure.in: Added better check for libwrap (the old way failed when
  libwrap was a dynamic library) and also included extraneous check for
  -lnsl after libwrap check (from head branch). Add -lwrap to new subst
  var WRAP_LIBS so we have more control over where it get's linked
  (dynamic libwrap causes problems when we link to programs that don't
  define certains globals that libwrap expects).
* build/top.mk: Added placeholder for WRAP_LIBS subst
* servers/slapd/Makefile.in: Added $(WRAP_LIBS) to the slapd and sslapd
  link command line specifically so it doesn't get thrown in with the rest
  of the LIBS.
* configure: rebuilt