Use "icon-fixed-width" to align sidebar items nicely.
Default to cyborg bootswatch, add (commented out) theme switcher.

Useful for quickly testing different themes, but not for production.
Increase date subtitle field size to fix wrapping.
Add THEME_CHANGER variable, set in debug, for easy theme testing.
me.rst: Fixup publication listing issue from 3.0.0 upgrade.