Flash 10的移除功能Loader.unloadAndStop()

這個方法好像是新的10才有支援，
之前用loader.unload()會有事件偵聽還佔記憶體，或其它難以移除的問題。
用Loader.unloadAndStop()似乎得到了新的解決之道。
呼叫unloadAndStop()會有以下的情況發生。

• Sounds are stopped.
• Stage event listeners are removed.
• Event listeners for enterFrame, frameConstructed, exitFrame, activate and deactivate are removed.
• Timers are stopped.
• Camera and Microphone instances are detached
• Movie clips are stopped.