code: function(username, password) {
          var c = null;
          Augmented.ajax({
            url: this.uri,
            method: "GET",
            user: username,
            password: password,
            success: function(data, status) {
              var p = new principal({
                fullName: data.fullName,
                id: data.id,
                login: data.login,
                email: data.email
              });
              c = new securityContext(p, data.permissions);
            },
            failure: function(data, status) {
              // TODO: Bundle this perhaps
              throw new Error("Failed to authenticate with response of - " + status);
            }
          });
          return c;
        }
docs: authenticate the user
  @method authenticate
  @param {string} username The name of the user (login)
  @param {string} password The password for the user (not stored)
  @returns {Augmented.Security.Context} Returns a security context or null is case of failure
  @memberof Augmented.Security.Client.ACL
  @throws Error Failed to authenticate