Remove Stdlib dependency

Author: proux01

Makefile.coq.local

@@ -0,0 +1,8 @@
+pre-all::
+	if command -v coqc > /dev/null && (coqc --version | grep -q '8.18\|8.19\|8.20') ; then \
+	  for f in $(shell grep "From Corelib" $$(find . -name "*.v") | cut -d: -f1) ; do \
+	     sed -i.bak $${f} -e 's/From Corelib/From Coq/' ; \
+	     sed -i.bak $${f} -e 's/PosDef/PArith/' ; \
+	     $(RM) $${f}.bak ; \
+	  done ; \
+	fi

theories/PFsection1.v

@@ -1,6 +1,6 @@
 (* (c) Copyright 2006-2016 Microsoft Corporation and Inria.                  *)
 (* Distributed under the terms of CeCILL-B.                                  *)
-From Coq Require Import RelationClasses.
+From Corelib Require Import RelationClasses.
 From mathcomp Require Import ssreflect ssrfun ssrbool eqtype ssrnat seq path.
 From mathcomp Require Import div choice fintype tuple finfun bigop prime finset.
 From mathcomp Require Import order.