Stop polluting namespace.

  "{0:.{precision}s}".format('hello world', precision=5)
I pretty sure it's because of the 'precision' keyword.
Still need to investigate further.

Issue1028

Hopefully this works with VC7.  If not, it should be pretty close.

I skipped the adding of libraries because it was harder and I'm less
confident about getting it right.  Also I'm not sure why they are required
now and weren't required before.

Applying without testing since I don't have Windows.  It
seems to make sense from a cursory review.

This makes the failing tests (test_unicodedata and, on OSX, test_hashlib) pass.

XXX However, I'm not sure that this is the right thing to do;
this behavior means that Unicode strings are automatically hashed as their
UTF-8 encoding.  Is that what we want?

but without it test_string passes.  I'm not sure why it was there.