Strip protocol part, present e.g. if in KDE + manual proxy mode.

[sdedic]

I've noticed bad behaviour in KDE when the system proxy is specified manually. The kioslaverc then contains settings like

ftpProxy=ftp://proxy.acme.com:80
httpProxy=http://proxy.acme.com:80
httpsProxy=http://proxy.acme.com:80
socksProxy=socks://proxy.acme.com:80

and the proxy string then contains not only port specification, but the protocol part as well. The error can be seen in Tools | Options, when System proxy is selected (and KDE has a manual system proxy) - the "Test connection" button action fails with hostname prefixed by http://.

This PR strips the PR part from the host string.

[matthiasblaesing]

Seems reasonable. The settings format seems a bit strange and this might be better in the KDE only part, but I can imagine people using that format in the http_proxy environment format. There might be an issue if people call their hosts like that, but then they will be in pain anyway.

Oh and the unittest failure in CSS look weird, I'll restart the test.

[matthiasblaesing]

Was a bit strange, restarting just the failing job moved the problem from CSS editor to option editor. Rerunning all tests (thus also rerunning the full build) fixed it.