Modify timestamp UnmarshalJSON for accurate time

Add documentation

timestamp.go

@@ -6,24 +6,24 @@ import (
 	"time"
 )
 
+// Timestamp struct for easily MarshalJSON/UnmarshalJSON unix timestamp to time.Time
 type Timestamp struct {
 	time.Time
 }
 
+// MarshalJSON converts golang time to unix timestam number
 func (t *Timestamp) MarshalJSON() ([]byte, error) {
 	ts := t.Time.Unix()
 	stamp := fmt.Sprint(ts)
-
 	return []byte(stamp), nil
 }
 
+// UnmarshalJSON converts unix timestamp to golang time
 func (t *Timestamp) UnmarshalJSON(b []byte) error {
 	ts, err := strconv.Atoi(string(b))
 	if err != nil {
 		return err
 	}
-
-	t.Time = time.Unix(int64(ts), 0)
-
+	t.Time = time.Unix(int64(ts/1000), 0)
 	return nil
 }