Unique proxy only by IP, not IP + PORT

[pioter83]

Describe the bug
Sometimes we provide our own Providers.

Some proxy providers rotate PORT and do not change IP, i.e.
monday: 1.2.3.4:8080 and 1.2.3.4:8081
tuesday: 1.2.3.4:8081
wednesday: 1.2.3.4:8080
thursday: 1.2.3.4:8080 and 1.2.3.4:8081

To Reproduce

• DB should also contain port in UNIQUE
  Class Meta:
  indexes = ( (('ip', 'port'), True), )

• jobs.py / def save_ip should contain port as well:
  where(ProxyIP.ip == p.ip, ProxyIP.port == p.port)

NOT sure if that's all, all if that doesn't make as mess.