add social thumbnial
{'login': 'philschmid', 'id': 32632186, 'node_id': 'MDQ6VXNlcjMyNjMyMTg2', 'avatar_url': 'https://avatars.githubusercontent.com/u/32632186?v=4', 'gravatar_id': '', 'url': 'https://api.github.com/users/philschmid', 'html_url': 'https://github.com/philschmid', 'followers_url': 'https://api.github.com/users/philschmid/followers', 'following_url': 'https://api.github.com/users/philschmid/following{/other_user}', 'gists_url': 'https://api.github.com/users/philschmid/gists{/gist_id}', 'starred_url': 'https://api.github.com/users/philschmid/starred{/owner}{/repo}', 'subscriptions_url': 'https://api.github.com/users/philschmid/subscriptions', 'organizations_url': 'https://api.github.com/users/philschmid/orgs', 'repos_url': 'https://api.github.com/users/philschmid/repos', 'events_url': 'https://api.github.com/users/philschmid/events{/privacy}', 'received_events_url': 'https://api.github.com/users/philschmid/received_events', 'type': 'User', 'site_admin': False}
[]
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# What does this PR do?

I added OpenGraph/ Twitter Card support to the docs to create nice social thumbnails.

![Bildschirmfoto 2021-04-07 um 08 36 50](https://user-images.githubusercontent.com/32632186/113821698-bac2ce80-977c-11eb-81aa-d8f16355857e.png)

To be able to add these I needed to install `sphinxext-opengraph`. I came across this [issue](https://github.com/readthedocs/readthedocs.org/issues/1758) on the readthedocs repo saying that since someone has built this plugin they are not integrating and providing documentation to it. That's why I added it for creating the documentation. The repository can be found [here](https://github.com/wpilibsuite/sphinxext-opengraph/tree/main).

P.S. It seemed that `make style` never ran for `docs/` i hope the changes are okay otherwise I'll revert it. 
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