Moved back to pg 0.18.4 (newer versions are not working correctly).

Gemfile.lock

@@ -248,7 +248,7 @@ GEM
       omniauth-oauth (~> 1.1)
     parser (2.3.1.2)
       ast (~> 2.2)
-    pg (0.20.0)
+    pg (0.18.4)
     pluginator (1.3.0)
     power_assert (0.3.1)
     powerpack (0.1.1)