update passlib url (#90)

thijstriemstra · asvetlov · commit e99ce6ba23b8 · 2017-07-24T09:58:54.000+03:00
diff --git a/docs/example_db_auth.rst b/docs/example_db_auth.rst
@@ -12,7 +12,7 @@ the `demo source`_.
     https://github.com/aio-libs/aiohttp_security/tree/master/demo
 
 .. _passlib:
-    https://pythonhosted.org/passlib/
+    https://passlib.readthedocs.io
 
 Database
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