Move argparse requirement to a separate requirements-py2.6.txt. py2.7 and above don't need this, and pypi was complaining about not finding argparse==1.2.1 on this decade's python.
Remove merge conflict and improve Read the Docs theme compatibility
Alter names so API docs more clearly related in nav. Add subheads for object lookup and search in api/index.rst
Add livehtml to makefile for those of us with sphinx-autobuild installed.