- use out ip to query country
- query country failed then use myip's country name
- fixed bug of checking proxy level
- support check cache
- optimize check?host= as concurrent, send to background
- support load exists cert firstly when tls enabled
- add default timeout
- add worker pool
- only fetch user's proxies
- remove auth config, every request must with auth token
- check ipv6 support
- add web