c-parser+autocorres: update Simpl links

Avoid redirects, link to current canonical version.

Signed-off-by: Gerwin Klein <gerwin.klein@proofcraft.systems>

tools/autocorres/doc/quickstart/document/root.bib

@@ -44,7 +44,7 @@
     journal = {Archive of Formal Proofs},
     month   = feb,
     year    = 2008,
-    url     = {https://www.isa-afp.org/entries/Simpl.shtml},
+    url     = {https://www.isa-afp.org/entries/Simpl.html},
     note    = {Formal proof development},
     ISSN    = {2150-914X},
 }

tools/autocorres/tools/release_files/README

@@ -112,7 +112,7 @@ This package contains:
     * Norbert Schirmer's Simpl language and associated VCG tool. The
       C parser translates C into Schirmer's Simpl language:
 
-        https://www.isa-afp.org/entries/Simpl.shtml
+        https://www.isa-afp.org/entries/Simpl.html
 
     * Code from SML/NJ, including an implementation of binary sets
       (Binaryset.ML) and the mllex and mlyacc tools

tools/c-parser/README.md

@@ -31,7 +31,7 @@ The translation tool builds on various open source projects by others.
    Sources for this are found in the Simpl/ directory.  The
    code is covered by an LGPL licence.
 
-   See <https://isa-afp.org/entries/Simpl.shtml>
+   See <https://isa-afp.org/entries/Simpl.html>
 
 2. Code from SML/NJ:
    - an implementation of binary sets (Binaryset.ML)

tools/c-parser/Simpl/README.md

@@ -10,4 +10,4 @@ Simpl
 This directory contains Norbert Schirmer's Simpl language and associated VCG
 tool. The code is covered by an LGPL licence.
 
-See <http://afp.sourceforge.net/entries/Simpl.shtml>
+See <https://www.isa-afp.org/entries/Simpl.html>