Add the Bootstrap SASS gem.
Add the Bootstrap basic template.
Inject the current controller and action into the page content so that CSS can be selectively applied to pages.
Override rails_utils to check for HighVoltage.
Add themes_on_rails for theme extensibility.
Inherit themes from superclasses.

This is needed for high_voltage to display the pages with the correct theme.
Factor out common application resources to a view helper.
Move the application template into the default theme.

We cannot allow theming and define a default layout at the same time since the layout is implicitly dependent on the CSS.
Write developer notes for how themes work in Coursemology.