Include different front-end/design frameworks

Saying that the only "design" option is Bootstrap is quite limiting and preferencial choice. It should provide options for people who aren't aware of different frameworks out there. Some of them might write their own front ends, since including a framework introduces (usually) layers of complexity and unnecessary bloat to codebases.

Added more choices:
- Topcoat
- Foundation

Both smaller than Bootstrap. It's good to have a choice and not unnecessarily enforce those.