WOPI detailed image for dev-docs

[mmattel]

References: https://github.com/owncloud/docs-ocis/pull/340 (Add wopi documentation)

Post a discussion with @rhafer, we decided to move the detailed wopi description image, which was a result of an intense discussion with @wkloucek, into an issue here so it is not lost and can be added to the dev docs by a someone (tm). The image is created with drawio.

Here is the original text that was added with the image:

:traefik_url: https://traefik.io/traefik/ :nginx_url: https://www.nginx.com :apache_url: https://www.apache.org

... With this image, administrators can get a more detailed view about the components involved down to a service level. It also includes steps triggered by the user and the requests and responses on a generic level. It shows how a reverse proxy fits into the picture. The reverse proxy is exemplary per level, where in reality, it usually is a redundant proxy environment configured per level. You can use any proxy of your choice like {traefik_url}[Traefik], {nginx_url}[nginx] or {apache_url}[Apache]. ...

@rhafer @micbar @dragotin @wkloucek fyi

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This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 10 days if no further activity occurs. Thank you for your contributions.

[mmattel]

keep open

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 10 days if no further activity occurs. Thank you for your contributions.

[mmattel]

keep alive

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 10 days if no further activity occurs. Thank you for your contributions.

[mmattel]

keep open

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 10 days if no further activity occurs. Thank you for your contributions.

[mmattel]

keep open