Preparing the release

CHANGELOG.md

+# Version 0.0.15
+
+- Better handling of mixed C/C++ code and `extern "C"` declarations
+- Compatibility with Frama-C 28.x Nickel
+
+# Version <= 0.0.14
+
+- See https://frama-c.com/fc-plugins/frama-clang.html

frama-clang.opam.template

 name: "frama-clang"
-version: "0.0.15-beta"
+version: "0.0.15"
 synopsis: "Frama-C plug-in based on Clang for parsing C++ files"
 description: """
 This Frama-C plug-in parse C++ files that may content ACSL++ annotations.
@@ -9,5 +9,5 @@ authors: [
   "Virgile Prevosto"
 ]
 license: "LGPL-2.1-only"
-homepage: "https://frama-c.com/frama-clang.html"
+homepage: "https://frama-c.com/fc-plugins/frama-clang.html"
 bug-reports: "https://git.frama-c.com/pub/frama-clang"