Update to Pelican 3.3 release

Some fixes and optimzations.  See the Pelican release notes here:

        http://blog.getpelican.com/pelican-3.3-released.html

You'll need to update your virtual env to use Pelican 3.3, ie:

    pip install -r requirements.txt -U
pelican.conf.py: Updates for Pelican 3.3

FILES_TO_COPY is deprecated, so we need to use STATIC_PATHS now.
The METADATA thing is needed to copy the file to a different path,
ie to the document root instead of the path its copied from.

See the docs:

        http://docs.getpelican.com/en/3.3.0/settings.html#basic-settings
Merge pull request #21 from alanorth/pelican-3.3

Update to Pelican 3.3