Expand message to show it as an attachment.
Expand message to show it as an attachment.

Rather than posting only the URL, this copies Slack's
internal integration behavior, expanding the message
to show it as an attachment.

Signed-off-by: David Calavera <b9b0c8e7f90ecf337f6797c4d2e0f1dd0dbc0324@gmail.com>

netlify/twickr