POT.py download link fixed

And yes, I fixed the download link for POT.py. It was pointed at POT.py.zip when the file was pot.py.zip.

I also fixed a slew of 404s in my org.mancer and SimpleChatServer javadocs: another case problem, in which the auto-generated subdirectories, through conspiracy by javadoc and Windows, were named all in uppercase while the links named them in lowercase. How nice of them.