[ADD] base: LGPL as possible module license

Keeping in mind than the AGPLv3 core still propagates the license to other
modules.
Fixes #6914

openerp/addons/base/module/module.py

@@ -302,6 +302,7 @@ class module(osv.osv):
             ('GPL-3', 'GPL Version 3'),
             ('GPL-3 or any later version', 'GPL-3 or later version'),
             ('AGPL-3', 'Affero GPL-3'),
+            ('LGPL-3', 'LGPL Version 3'),
             ('Other OSI approved licence', 'Other OSI Approved Licence'),
             ('Other proprietary', 'Other Proprietary')
         ], string='License', readonly=True),