[QA] enabling mediaviewer and drawio not documented

[jnweiger]

Seen with web-1.0.2 in owncloud server 10.6.0

Follow the setup instructions at https://owncloud.github.io/clients/web/deployments/oc10-app/

• visit Settings -> New Design
• click on a JPG file in the Photos folder.
• a download dialog opens, as config.json only has "apps": [ "files" ]

Expected behaviour:

• the instructions spell out the names of mediaviewer and drawio sub-apps in the apps list.
• mediaviewer opens without downloading.

[jnweiger]

Same issue with duplicate(?) instructions at https://github.com/owncloud/web/blob/master/docs/deployments/oc10-app.md

These work:

  "apps": [
    "files",
    "draw-io",
    "markdown-editor",
    "media-viewer"
  ]