fix links to Coq standard library in coqdoc output

Also switch how this is patched into the Makefile while we're at it.

create_makefile.sh

@@ -16,16 +16,9 @@ else
 	sed -i 's|$(notdir $(^:.vo=))|$(addprefix rt., $(subst /,., $(^:.vo=)))|g' Makefile
 fi
 
-
-# Fix 'make html' so that it parses comments and has links to ssreflect.
-if [ "$(uname)" == "Darwin" ]; then
-	sed -i '' 's|-interpolate -utf8|--interpolate --utf8 --plain-comments --parse-comments --external https://math-comp.github.io/math-comp/htmldoc/ mathcomp|g' Makefile
-else
-	sed -i 's|-interpolate -utf8|--interpolate --utf8 --plain-comments --parse-comments --external https://math-comp.github.io/math-comp/htmldoc/ mathcomp|g' Makefile
-fi
-
 # Patch Makefile.coqdocjs for pretty documentation targets
 printf "\n# Include pretty documentation targets\ninclude scripts/coqdocjs/Makefile.coqdocjs" >> Makefile
 
-# Patch HTML target to switch out color
+# Patch HTML target to switch out color, and 
+# so that it parses comments and has links to ssreflect.
 patch -s < scripts/Makefile.patch

scripts/Makefile.patch

 --- Makefile.orig	2019-10-15 22:37:51.000000000 +0200
 +++ Makefile	2019-10-15 22:33:50.000000000 +0200
+@@ -179,7 +179,7 @@
+ # these flags do NOT contain the libraries, to make them easier to overwrite
+ COQFLAGS?=-q $(OTHERFLAGS) $(COQEXTRAFLAGS)
+ COQCHKFLAGS?=-silent -o $(COQCHKEXTRAFLAGS)
+-COQDOCFLAGS?=-interpolate -utf8 $(COQDOCEXTRAFLAGS)
++COQDOCFLAGS?=-interpolate -utf8 --parse-comments --coqlib https://coq.inria.fr/distrib/current/stdlib/ --external https://math-comp.github.io/math-comp/htmldoc/ mathcomp $(COQDOCEXTRAFLAGS)
+ 
+ COQDOCLIBS?=$(COQLIBS_NOML)
+ 
 @@ -422,6 +422,9 @@
  	$(HIDE)mkdir -p html
  	$(HIDE)$(COQDOC) \