add weboob_lint.py script

tools/weboob_lint.py

@@ -0,0 +1,10 @@
+#!/usr/bin/env python
+
+from weboob.core.backends import BackendsLoader
+
+loader = BackendsLoader()
+loader.load_all()
+
+backends_without_icons = [name for name, backend in loader.loaded.iteritems() if backend.icon_path is None]
+if backends_without_icons:
+    print 'Backends without icons: %s' % backends_without_icons