Add ability to select printer

[felixmulder]

Need to be able to select between:

• power printer
• user printer
• refined printer

Currently the user can see types like SkolemType etc, this is confusing and not very helpful. We still want to keep this for development purposes - but the user facing one needs to be properly implemented.

[smarter]

I added a -Yprint-debug option in #2835 for this purpose, doesn't do much yet.

[smarter]

Closing given the previous comment, separate issues should be open if we see something weird being printed in error messages etc.