Display tags for questions#show view

~~WIP~~

Goal: to display tag info on Q&A views so designers can eventually make them look nice and usable.

Ready for QA:

- visit a url like `/answers/12`
- check that at least one tag is displayed beneath the Q&A text
- check that the link takes you to the page that displays all questions for that tag (e.g `/tags/SOME_ID`
I prefer `titleize` to capitalize