Login via OpenID-2.0 (#618)

vendor/github.com/yohcop/openid-go/README.md

@@ -0,0 +1,38 @@
+# openid.go
+
+This is a consumer (Relying party) implementation of OpenId 2.0,
+written in Go.
+
+    go get -u github.com/yohcop/openid-go
+
+[![Build Status](https://travis-ci.org/yohcop/openid-go.svg?branch=master)](https://travis-ci.org/yohcop/openid-go)
+
+## Github
+
+Be awesome! Feel free to clone and use according to the licence.
+If you make a useful change that can benefit others, send a
+pull request! This ensures that one version has all the good stuff
+and doesn't fall behind.
+
+## Code example
+
+See `_example/` for a simple webserver using the openID
+implementation. Also, read the comment about the NonceStore towards
+the top of that file. The example must be run for the openid-go
+directory, like so:
+
+    go run _example/server.go
+
+## App Engine
+
+In order to use this on Google App Engine, you need to create an instance with a custom `*http.Client` provided by [urlfetch](https://cloud.google.com/appengine/docs/go/urlfetch/).
+
+```go
+oid := openid.NewOpenID(urlfetch.Client(appengine.NewContext(r)))
+oid.RedirectURL(...)
+oid.Verify(...)
+```
+
+## License
+
+Distributed under the [Apache v2.0 license](http://www.apache.org/licenses/LICENSE-2.0.html).