Updated cleaner to check for dir existing.

cleaner.d

@@ -13,6 +13,7 @@ import std.datetime;
 const EXTRACTS_DIR = "extracts";
 
 int main() {
+    if (!exists(EXTRACTS_DIR)) return 0;
     immutable SysTime now = Clock.currTime();
     foreach (DirEntry entry; dirEntries(EXTRACTS_DIR, SpanMode.shallow, false)) {
         Duration age = now - entry.timeLastModified();