enhancement: make a small noise when closing lid to remind user if NoSleep is enabled

I sometimes leave NoSleep enabled, then place my laptop in my bag, where it 
overheats.  I suggest a small user choosable sound to play when the lid is 
closed, to remind the user if NoSleep is active

What steps will reproduce the problem?
1. Enable NoSleep
2. Forget that it is enabled
3. Close the lid
4. Put laptop in rucksack
5. Laptop overheats

What is the expected output? What do you see instead?
1. Enable NoSleep
2. Forget that it is enabled
3. Close the lid
4. Laptop makes a small noise 
5. I remember NoSleep is enabled, before frying my laptop

What version of the product are you using? On what operating system?
(if you don't know how to get a version number, enter "kextstat|grep -i
nosleep" in Terminal.app, without quotes)

1.3.0

Please provide any additional information below.

PS - thanks for a very useful app!

Original issue reported on code.google.com by tomhan...@gmail.com on 6 Jul 2014 at 11:04

Mathias91 / macosx-nosleep-extension

enhancement: make a small noise when closing lid to remind user if NoSleep is enabled #131