[FIX] ir_ui_view: Active (boolean) should not be required

If so, impossible to uncheck the box in the webclient

openerp/addons/base/ir/ir_ui_view.py

@@ -167,7 +167,7 @@ class view(osv.osv):
   (<xpath/>) are applied, and the result is used as if it were this view's
   actual arch.
 """),
-        'active': fields.boolean("Active", required=True,
+        'active': fields.boolean("Active",
             help="""If this view is inherited,
 * if True, the view always extends its parent
 * if False, the view currently does not extend its parent but can be enabled