When resetting, reset the chunk dictionary and the counted chunk set as well.

Author: Mallory Paine

FastImageCache/FICImageTable.m

@@ -677,6 +677,8 @@ - (void)reset {
     [_inUseEntries removeAllObjects];
     [_MRUEntries removeAllObjects];
     [_sourceImageMap removeAllObjects];
+    [_chunkDictionary removeAllObjects];
+    [_chunkSet removeAllObjects];
 
     [self _setEntryCount:0];
     [self saveMetadata];