Resolve "Implement 'Short Description' field on posts"
- Show post summary in post list if available, fall back to truncated post body
- Use post summary in SEO if available, fall back to truncated post body
- Added post summary field in post creation form
Can be tested on:
- post creation: https://hivean.com/submit.html
- post preview: https://hivean.com/created/peakd
Closes #27 (closed)