Search of ad units in catalog, automatic ban of phishing/malware ads, improved geo-filters and IP counters

1. Advertisers can search ad units in the catalogue (and in their campaigns' targeting tab as well).  
2. Google Safe Browsing Lookup API is used to automatically ban malicious ads.
3. Our geo-filtering mechanism is still extravagant but at least it prevents advertising budgets from being spent on ad units that have less than 30% of traffic from the wanted countries now.
4. Unique IPs expire in 24 hours from their occurrence (not at midnight as it was before).