Use bottom menu to flip facets

Context

We need some way to flip from one facet to another, regardless of the implementation of the facet itself.

Decision

Display alternative facets in the bottom menu.

Consequences

Pro

• Easy to implement, no extra widgets needed

Contra

• Might be too many facets there
• There are not that many facets right now, we do not care so far
• Later we can expand this to a special menu or whatever