feat: add a Salut opam package

salut.opam

+opam-version: "2.0"
+synopsis: "A Lustre API for SASA"
+description: """\
+SASA is a *Self-stabilizing Algorithms SimulAtor*. Algorithms in SASA
+are provided in OCaml. 
+
+With Salut, one can provide them in lustre and perform model-checking
+(with lesar or kind2).
+"""
+maintainer: "erwan.jahier@univ-grenoble-alpes.fr"
+authors: "Erwan Jahier and Gabriel B. Sant'Anna"
+license: "CeCILL-2.1"
+homepage:
+  "https://gricad-gitlab.univ-grenoble-alpes.fr/verimag/synchrone/sasa"
+bug-reports:
+  "https://gricad-gitlab.univ-grenoble-alpes.fr/verimag/synchrone/sasa/issues"
+depends: [
+  "sasa"
+  "kind2" { < "1.6" }
+]
+build: ["dune" "build"]
+install: ["dune" "install"]
+post-messages:
+  "The last version can be obtained via (opam repo add) http://www-verimag.imag.fr/DIST-TOOLS/SYNCHRONE/opam-repository/"
+dev-repo:
+  "git+https://gricad-gitlab.univ-grenoble-alpes.fr/verimag/synchrone/sasa.git"

sasa.opam

@@ -26,7 +26,6 @@ depends: [
   "rdbg" { >= "1.194" }
   "lustre-v6"
   "lutin"
-  "kind2" { < "1.6" }
   ]
 build: [make "build"]
 install: ["dune" "install"]