return history properly sorted

models.go

@@ -12,6 +12,12 @@ type JobVersion struct {
 	SubmitTime int
 }
 
+type History []JobVersion
+
+func (h History) Len() int           { return len(h) }
+func (h History) Swap(i, j int)      { h[i], h[j] = h[j], h[i] }
+func (h History) Less(i, j int) bool { return h[i].Version < h[j].Version }
+
 type Version struct {
 	Version int `json:"Version,string"`
 }