/// <summary>
/// Takes an existing httpwebrequest and modifies its headers according to
/// the authentication system used.
/// </summary>
/// <param name="request"></param>
/// <returns></returns>
public override void ApplyAuthenticationToRequest(HttpWebRequest request)
{
string oauthHeader = OAuthUtil.GenerateAuthorizationHeader(
request.RequestUri, ConsumerKey, ConsumerSecret, null, null, request.Method);
request.Headers[HttpRequestHeader.Authorization] = oauthHeader;
}