Issue 351: Reimplement OAuth2 - Step 2 (Auth PCL - only data types)

Src/GoogleApis.Auth/GoogleJsonWebSignature.cs

+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace Google.Apis.Auth
+{
+/// <summary>
+/// Google JSON Web Signature as specified in https://developers.google.com/
accounts/docs/OAuth2ServiceAccount.
+/// </summary>
+public class GoogleJsonWebSignature
+{
+// TODO(peleyal): We should provide a way to verify JWS.
+// Take a look at: https://github.com/googleplus/gplus-verifytoken-cshar
p/blob/master/verifytoken.ashx.cs.
+
+/// <summary>
+/// The header as specified in https://developers.google.com/accounts/do
cs/OAuth2ServiceAccount#formingheader.
+/// </summary>
+public class Header : JsonWebSignature.Header
+{
+}
+
+/// <summary>
+/// The payload as specified in·
+/// https://developers.google.com/accounts/docs/OAuth2ServiceAccount#for
mingclaimset.
+/// </summary>
+public class Payload : JsonWebSignature.Payload
+{
+/// <summary>
+/// a space-delimited list of the permissions the application reques
ts or <c>null</c>.
+/// </summary>
+[Newtonsoft.Json.JsonPropertyAttribute("scope")]
+public string Scope { get; set; }
+
+/// <summary>
+/// The email address of the user for which the application is reque
sting delegated access.
+/// </summary>
+[Newtonsoft.Json.JsonPropertyAttribute("prn")]
+public string Prn { get; set; }
+}
+}
+}