Add a "Privacy" page and link to public stats (fixes #605)

Live preview: http://bitcointest3.us.to/en/privacy

Note: The link to public stats is expected to be not working on the live preview because "/stats/" only exists on https://bitcoin.org/stats/.

Public stats seem to be working fine so now may be a good time to add a link to it and a "Privacy" page. I've had the confirmation that as long as we are not using cookies and not collecting personal data - as in data identifying a real person, this simple "Privacy" page is appropriate.

This pull request also makes some reorganization in the footer and CSS otherwise space would be missing.
I think "last bit" should be "last byte" or "last octet", although I guess 'last bit' could also mean 'last [small amount]'.