add missing semicolon to attribution, comment out empty category and topic
templates: add more guidance information.

- Fix double-secret commenting `# #`
- Explicity label both category and topics to be completed with a link
  to appropriate section of the meta data docs
- Request tests for example queries and some negative samples.
templates/Example.pm: down with tabs.
Merge pull request #1182 from duckduckgo/zaahir/template-fix

add missing semicolon to attribution, comment out empty category and topic