List Campaign Contacts

Lists campaign contacts based on filters.

Common filters are limit and offset.

Receives filters as query string parameters corresponding to boolean values.

Filter options are:

• delivered (true/false) - will return campaign contacts that received the campaign.
• responded (true/false) - will return campaign contacts that responded to the campaign.
• unsubscribed (true/false) - will return campaign contacts that unsubscribed after the campaign.
• clicked_link (true/false) - will return campaign contacts that clicked a link from the campaign.

The filters can be grouped, which allows users to get, for instance, all contacts
that responded to a campaign and clicked on a link, or contacts that received a campaign
and unsubscribed after that.