Article card about cardboard

[habdelra]

@dnaidionov please note that I cleaned up these fields' descriptions and I removed the narrative container. that will have to happen as a separate story after ember conf.

[habdelra]

this conversation slack is also germain in terms of publishing: https://cardstacksyndicate.slack.com/archives/GA647K66R/p1551476986025900

[habdelra]

@dnaidionov I notice that the description field is one that is displayed only in the embedded view. I wonder if we need to pull the trigger on the framework functionality to be able to edit your card when viewing it in different formats. similar to how AIA worked /cc @ef4

[habdelra]

Filed cardstack/cardstack#679 to deal with editing an article in the embedded format

[dnaidionov]

@habdelra description is displayed in both views, so that would address the problem of not having the "embedded view editor" right now, but after emberconf we should totally implement the editor for embedded mode