Merge pull request #11 from colin-axner/colin/memo-reset

Add (forceful) Reset function to memo

memo/memo.go

@@ -67,3 +67,13 @@ func (memo *Memo) Get() (value interface{}, err error) {
 	}
 	return memo.cache.res.value, memo.cache.res.err
 }
+
+// Reset forcibly resets the cache to nil without checking if the cache
+// duration has elapsed.
+func (memo *Memo) Reset() {
+	defer memo.mu.Unlock()
+	memo.mu.Lock()
+
+	memo.cache = nil
+	memo.lastCache = time.Now()
+}