Add Open Graph support

[chayev]

Using a website reference, check if that website has proper Open Graph support. This would allow you to confirm that your site will display properly when shared.

Use case: yurl opengraph validate

Alias: og

Output:

Valid - return whether the Open Graph data format is valid (based on Reference)
Invalid - return if the Open Graph data format is invalid based on above reference
Not Found - tags not found