templates: freshen for current use.

- Add explicit answer_type and caching settings.
- Point to metadata documentation to help complete section.
- Rearrange metadata to match documentation.
- Update attribution with better example strings.
- Place guard clause before work clause in example code.
Example templates: Spice doesn't have answer_type.

- Remove 'zci answer_type' from templates.
- Rename 'zci is_cached' to 'spice is_cached'.
- Remove 'spice answer_type' from testwhere it appears.
Merge pull request #1134 from mwmiller/update_templates

templates: freshen for current use.