Add automatic search and replace for blocked URIs in content

[tollmanz]

With the current state of the WP CLI commands, we can easily identify blocked URIs that have working HTTPS equivalents. WP CLI provides the sexy search-replace command. If we have information on blocked URIs and their working HTTPS equivalents, we can easily run automated commands to remove those URIs from the content.

The application of this would be to set this on a cron schedule to periodically activate the plugin to search for mixed content issues, then automatically fix blocked URIs in the content.