Lowercase the host part when normalising URI.

src/oauth_uri.erl

@@ -16,8 +16,8 @@
 
 normalize(URI) ->
   case http_uri:parse(URI) of
-    {Scheme, UserInfo, Host, Port, Path, Query} ->
-      normalize(Scheme, UserInfo, Host, Port, [Path, Query]);
+    {Scheme, UserInfo, Host, Port, Path, _Query} ->
+      normalize(Scheme, UserInfo, string:to_lower(Host), Port, [Path]);
     Else ->
       Else
   end.