Licensing info both in README and in LICENCE

AUTHORS

@@ -22,4 +22,3 @@ with contributions of
     Asma Tafat
     Piotr Trojanek
     Makarius Wenzel
-

LICENSE

@@ -14,6 +14,10 @@ of the Library that is distributed under the conditions defined in clause
 however invalidate any other reasons why the executable file might be
 covered by the GNU Lesser General Public License.
 
+The files src/util/extmap.ml{i} are derived from the sources of
+OCaml 3.12 standard library, and are distributed under the GNU
+LGPL version 2 (see file OCAML-LICENSE).
+
 Icon sets for the graphical interface of Why3 are subject to specific
 licenses, some of them may forbid commercial usage. These specific
 licenses are detailed in files share/icons/*/*.txt

README

@@ -42,6 +42,10 @@ The files src/util/extmap.ml{i} are derived from the sources of
 OCaml 3.12 standard library, and are distributed under the GNU
 LGPL version 2 (see file OCAML-LICENSE).
 
+Icon sets for the graphical interface of Why3 are subject to specific
+licenses, some of them may forbid commercial usage. These specific
+licenses are detailed in files share/icons/*/*.txt
+
 INSTALLATION
 ============