Complete the testing for decoding datetime with UTC offset

Kudos to @nathany who wrote:

> It looks like the simple struct below should include a few more fields
> and answer should do a comparison of these to complete the testing.

in his code review for Pull Request #182.

decode_test.go

@@ -16,8 +16,8 @@ age = 250
 andrew = "gallant"
 kait = "brady"
 now = 1987-07-05T05:45:00Z
-nowCanada = 2017-06-22T02:14:36-06:00
-nowChina = 2017-06-22T16:15:21+08:00
+nowEast = 2017-06-22T16:15:21+08:00
+nowWest = 2017-06-22T02:14:36-06:00
 yesOrNo = true
 pi = 3.14
 colors = [
@@ -40,6 +40,8 @@ cauchy = "cat 2"
 		Pi      float64
 		YesOrNo bool
 		Now     time.Time
+		NowEast time.Time
+		NowWest time.Time
 		Andrew  string
 		Kait    string
 		My      map[string]cats
@@ -55,11 +57,21 @@ cauchy = "cat 2"
 	if err != nil {
 		panic(err)
 	}
+	nowEast, err := time.Parse("2006-01-02T15:04:05-07:00", "2017-06-22T16:15:21+08:00")
+	if err != nil {
+		panic(err)
+	}
+	nowWest, err := time.Parse("2006-01-02T15:04:05-07:00", "2017-06-22T02:14:36-06:00")
+	if err != nil {
+		panic(err)
+	}
 	var answer = simple{
 		Age:     250,
 		Andrew:  "gallant",
 		Kait:    "brady",
 		Now:     now,
+		NowEast: nowEast,
+		NowWest: nowWest,
 		YesOrNo: true,
 		Pi:      3.14,
 		Colors: [][]string{