Add event featured/og image

[lukefretwell]

• Dimensions: 1200x630

• Example page: https://citycamp.com/events/atlanta-ga-united-states/

• Reference: https://ogp.me/#structured

• Add conditional code for featured/og image

• Ensure OG code is addressed (see below)

• Add image upload to form (add dimensions to field label) (https://citycamp.com/events/new)

Code:

<meta property="og:image" content="http://example.com/ogp.jpg" />
<meta property="og:image:secure_url" content="https://secure.example.com/ogp.jpg" />
<meta property="og:image:type" content="image/jpeg" />
<meta property="og:image:alt" content="A shiny red apple with a bite taken out" />

Screenshot from @Shaunm44: