Patched to support Linux

Hi Vitalik,
These are the changes that I found to be necessary to support Ubuntu. I had to remove support for one of the AES block cipher modes (CTR). I also pulled bitcoin.py and bitcointest.py out of the pyelliptic folder as per the issue that we faced the last time we tried to test my patches.
I won't be offended if you reject this pull request; I'm just offering my changes.
Thanks,
Jonathan