Proxy detection fixes

Small fixes for proxy detection issues:

- SOCKS proxy type on OSX 10.7 and 10.8 (didn't test 10.6) was reported as string "SOCKS5" instead of "socks"
- Chrome on Windows, if proxy auto-detection is selected in the system settings, reported proxy port as "port_number;DIRECT" or "port_number;PROXY". This happened when JS code in PAC file returns multiple entries, e.g. "PROXY host:port_number; DIRECT". Space symbol between entries are always removed by Chrome.
- If "use the same proxy for all protocols" is selected in IE settings and we ask for proxy settings for a HTTPS link, then no proxy were returned.