Change HTTP to HTTPS

[Voello]

When a file is uploaded, the tool adds a hyperlink in the author and source fields of the file description to http://www.geograph.org.uk/. Geograph nowadays uses HTTPS, which is preferred on Wikimedia for links if it is available. Generally, after every upload using the tool, SchlurcherBot will have to fix every URL to https. It would be very simple just to fix the tool so it links to https://www.geograph.org.uk/.

[Magnus Manske]

This should be done now, please re-open if not