Showcase sites need to be updated; one w/ redirects.

[alkasm]

The following sites don't work:

• https://explore.visitsarasota.org
• http://www.roboterwelt.de

The following site seems to have been eaten by malware and is giving redirects:

• http://webonise.co.uk/

A few of the other sites have also been updated, so the thumbnails might be do well with an update.

[CodexLink]

Hello, I think this one needs to be in Pull Request. Please do fork this project, and make changes from your forked project. Then propose your changes to the main repository/project. Glad this would help you since a lot of issues are not being checked or likely being ignored due to rules are not followed.