fix `conf.py` path mods and add `roles.py` install info
move theme into package (so `setup.py` can find it?)
ignore `dist/` (and *don't* ignore `.gitignore`!)
move Python support modules down into new theme package
add `distribute_setup.py` (in case user doesn't have it)
remove unused Exo font
move theme contents down into named subdir

We want Sphinx to look for the theme `agoraplex` *under* the
`agoraplex.themes.sphinx` directory, otherwise have to name
the theme something too generic, like... `sphinx` :-p