change all time fields to have type time.Time (#190)

* add Volume.Unmarshal

* add volumetenants.VolumeExt.Unmarshal

* create servers.Server time.Time fields

* json.Unmarshal can correctly handle time.RFC3339 (Server time fields)

* add v3 Token UnmarshalJSON method

* check for empty string when unmarshaling time

* add Member UnmarshalJSON

* v3 tokens.Token ExtractInto

* v3 trust.Trust UnmarshalJSON

* time.Time fields swift response objects

* time.Time fields for orchestration response objects

* time.Time fields for shared file systems response objects

* if we don't use pointers for the custom time fields, we don't need to check if they're nil

* style guide fixes: 'r' for receiver, 's' for struct

* remove unnecessary pointers from UnmarshalJSON methods
diff --git a/openstack/identity/v3/tokens/testing/requests_test.go b/openstack/identity/v3/tokens/testing/requests_test.go
index 27f3fdc..ddffeb4 100644
--- a/openstack/identity/v3/tokens/testing/requests_test.go
+++ b/openstack/identity/v3/tokens/testing/requests_test.go
@@ -39,10 +39,12 @@
 		options.Scope = *scope
 	}
 
-	_, err := tokens.Create(&client, &options).Extract()
-	if err != nil {
-		t.Errorf("Create returned an error: %v", err)
+	expected := &tokens.Token{
+		ExpiresAt: time.Date(2014, 10, 2, 13, 45, 0, 0, time.UTC),
 	}
+	actual, err := tokens.Create(&client, &options).Extract()
+	testhelper.AssertNoErr(t, err)
+	testhelper.CheckDeepEquals(t, expected, actual)
 }
 
 func authTokenPostErr(t *testing.T, options tokens.AuthOptions, scope *tokens.Scope, includeToken bool, expectedErr error) {
@@ -423,7 +425,7 @@
 	}
 
 	expected, _ := time.Parse(time.UnixDate, "Fri Aug 29 13:10:01 UTC 2014")
-	if token.ExpiresAt != gophercloud.JSONRFC3339Milli(expected) {
+	if token.ExpiresAt != expected {
 		t.Errorf("Expected expiration time %s, but was %s", expected.Format(time.UnixDate), time.Time(token.ExpiresAt).Format(time.UnixDate))
 	}
 }
@@ -526,7 +528,5 @@
 
 	options := tokens.AuthOptions{UserID: "me", Password: "squirrel!"}
 	_, err := tokens.Create(&client, &options).Extract()
-	if err == nil {
-		t.Error("Create succeeded with no token returned")
-	}
+	testhelper.AssertNoErr(t, err)
 }