Post summary box causes confusion

[tgaffey]

Feedback from a teacher: "Does the summary box have any purpose? AFAIK there's no way for students to see it. Is it just for us if we want to put a summary for our own organization? If so, can it get moved down/hidden? It's where most people would expect to type their post, and I constantly have to remind students and have them edit/repost since they're putting their posts in there, rather than a content block. On the same lines, could we have a markdown block open by default? Would save some time/clicks/mistakes."

[themightychris]

Remedies:

Front-end

• Hide summary field by default, make available under an "add summary" toolbar button
• Explain post summary better in placeholder text
• Make blog posts actually use summary when set on blog feeds
• Include a markdown content item by default, automatically delete if not populated
• Discourage empty blog posts with a warning

Back-end

• Use a migration to check for blog posts with summary but no content, move summary to a markdown content item and clear summary

[ryon]

Front-end work here JarvusInnovations/emergence-skeleton#268