added cache set and get

Author: dstpierre

cache.go

@@ -0,0 +1,26 @@
+package backend
+
+import "encoding/json"
+
+func CacheGet(token, key string, v interface{}) error {
+	var s string
+	if err := Get(token, "/sudo/cache?key="+key, &s); err != nil {
+		return err
+	}
+	return json.Unmarshal([]byte(s), v)
+}
+
+func CacheSet(token, key string, v interface{}) error {
+	b, err := json.Marshal(v)
+	if err != nil {
+		return err
+	}
+	data := new(struct {
+		Key   string `json:"key"`
+		Value string `json:"value"`
+	})
+	data.Key = key
+	data.Value = string(b)
+	var ok bool
+	return Post(token, "/sudo/cache", data, &ok)
+}