Small usage explanation

README.markdown

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+Go-OpenID
+=========
+
+About
+-----
+
+Go-OpenID is an attempt to implement OpenID in Golang.
+
+Usage
+-----
+
+        var o = new(openid.OpenID)
+        o.Identifier = "https://www.google.com/accounts/o8/id"
+        o.Realm = "http://example.com"
+        o.ReturnTo = "/loginCheck"
+        url := o.GetUrl()
+
+Now you have to redirect the user to the url returned. The OP will then forward the user back to you. To check the identity, do that:
+
+        var o = new(openid.OpenID)
+        o.ParseRPUrl(URL)
+        grant, err := o.Verify()
+
+grant is true if the user is authenticated, false otherwise. URL must contain the encoded content provided by the OP.
+
+Once o.ParseRPUrl(URL) is executed, all the information provided by the OP are in the map o.Params. For instance you get the identity with:
+
+     o.Params["openid.claimed_id"]
+