Minor changes regarding credits consumption

Starting June 1, 2020, the following changes will apply:

Bulk endpoints will consume 1 credit plus as many credits as IP addresses you input. Currently, it is consuming as many credits as IP addresses you input. The difference is one additional credit per bulk endpoint call.

Looking up private IP addresses will consume 1 credit. Currently, performing a lookup for a private IP address is free of charge.

The change should make almost no differences for legitimate usages of our API but will allow us to keep the infrastructure safe and prevent some recent abuses we noticed.