[README.md] Fix license from LGPL to BSD-clause 2

README.md

@@ -17,7 +17,7 @@ transmission.
 An efficient caching mechanism avoid useless data recomputation and a
 simple built-in language can be used to control the graph actions.
 
-It is released under the [LGPL-3](COPYING.LESSER) license.
+It is released under the [BSD-clause 2](COPYING.LESSER) license.
 
 
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