Don't use PyPI mirrors when installing packages

The implementation of a content delivery network (CDN) for PyPI has
significantly improved PyPI's performance. It is now faster and more
reliable to use the CDB and PyPI's mirrors.
Discontinue use of distribute_setup.py

Most users will already have distribute or setuptools installed. Users
who don't likely have not installed them intentionally.
Upload distribution when registering to PyPI

After registering a new version on PyPI, immediately upload the source
distribution package.
Update service badges for README

Adds a badge for latest version on PyPI, located in the introduction.
Update change log for next release

Document changes for 0.3 release
Version increment to 0.3

Update version number to 0.3 for new release.