Remove exemplar for now. (#112)

* Remove exemplar for now.

* Refresh go.sum.
diff --git a/equivalence_test.go b/equivalence_test.go
index a7bbff9..e2e67e2 100644
--- a/equivalence_test.go
+++ b/equivalence_test.go
@@ -25,7 +25,6 @@
 	"time"
 
 	"contrib.go.opencensus.io/exporter/ocagent"
-	"go.opencensus.io/metric/metricdata"
 	"go.opencensus.io/stats"
 	"go.opencensus.io/stats/view"
 	"google.golang.org/api/option"
@@ -193,13 +192,6 @@
 							Max:            500,
 							Mean:           125.9,
 							CountPerBucket: []int64{0, 1, 0, 0, 0, 0, 0},
-							ExemplarsPerBucket: []*metricdata.Exemplar{
-								nil,
-								{
-									Value: 125.9, Timestamp: startTime.Add(time.Duration(1+i) * time.Second),
-								},
-								nil, nil, nil, nil, nil,
-							},
 						},
 					},
 				},
diff --git a/go.sum b/go.sum
index 883826d..1fb117f 100644
--- a/go.sum
+++ b/go.sum
@@ -8,6 +8,8 @@
 contrib.go.opencensus.io/exporter/ocagent v0.4.7/go.mod h1:+KkYrcvvEN0E5ls626sqMv8PdMx2931feKtzIwP01qI=
 contrib.go.opencensus.io/exporter/ocagent v0.4.8-0.20190319160651-559ddb1ac74c h1:r42Bz1f0psj8my3PRFk/T7d6sI+E7cm7touVR5xsjZQ=
 contrib.go.opencensus.io/exporter/ocagent v0.4.8-0.20190319160651-559ddb1ac74c/go.mod h1:+KkYrcvvEN0E5ls626sqMv8PdMx2931feKtzIwP01qI=
+contrib.go.opencensus.io/exporter/ocagent v0.4.8 h1:lXKyRBciToQaTncNnT+SnpBSW1YJ6oJAGv7MqAqxBT8=
+contrib.go.opencensus.io/exporter/ocagent v0.4.8/go.mod h1:+KkYrcvvEN0E5ls626sqMv8PdMx2931feKtzIwP01qI=
 contrib.go.opencensus.io/resource v0.0.0-20190131005048-21591786a5e0 h1:ICrSnXeuT4427bpR8X9I7GxiyT4X5qgLtFT7m1IjK2c=
 contrib.go.opencensus.io/resource v0.0.0-20190131005048-21591786a5e0/go.mod h1:F361eGI91LCmW1I/Saf+rX0+OFcigGlFvXwEGEnkRLA=
 dmitri.shuralyov.com/app/changes v0.0.0-20180602232624-0a106ad413e3/go.mod h1:Yl+fi1br7+Rr3LqpNJf1/uxUdtRUV+Tnj0o93V2B9MU=