Change the way we store version info.

With the ``ansi2html/version.py`` approach, I ran into dependency
issues.  Running 'python setup.py install' would fail because it would
try to import ansi2html.version and inadvertently start importing
dependencies like 'six' and 'ordereddict' before they had themselves
been installed.

By keeping it in the setup.py, we can get around that.  We can still
access the version info at runtime with setuptools' pkg_resources.

/cc @hartwork
1.0.1
Merge branch 'release/1.0.1' into develop
Add an upload command to the Makefile.