HTTPS support for IP address resolver

[scootergrisen]

Suggest changing:
"Default: ​http://ip.filezilla-project.org/ip.php"

to:
"Default: ​https://ip.filezilla-project.org/ip.php"

So all links in PO file use HTTPS

[scootergrisen]

Also maybe the link should be replaced with a placeholder if the link is always the same in all PO files.

So from:
"Default: ​http://ip.filezilla-project.org/ip.php"
To:
"Default: %s"

Something like that if the translators don't need to change it, and so it can't be changed my translators by accident.

[Tim Kosse]

The resolver cannot handle HTTPS, only HTTP.

[scootergrisen]

Great.