Time out if IP Geolocation not reachable

[sonertari]

Otherwise, the request waits indefinitely, hence the Software Sources window gets frozen. See the documentation for request timeouts.

Currently, https://api.ip2location.io is not reachable where I am (it's been a few hours already). I am not sure if this is temporary, or if it's due to my network, but whatever the reason is, the Software Sources window should not get frozen.

I am not sure if this pr should be against the master branch, but it is the only active branch.

[sonertari]

Btw, the message field of the response from https://api.ip2location.io reads (I finally get responses on the web browser sometimes, but still not in the python script):

Limit to 1,000 queries per day. Sign up for a Free plan at https://www.ip2location.io to get 30K queries per month.

I hope we are not affected by this, but I am just a user.