def customers(limit=0, firstName=nil, lastName=nil, email=nil)
      options = {}
      if firstName
        options[:firstName] = firstName
      end
      if lastName
        options[:lastName] = lastName
      end
      if email
        options[:email] = email
      end

      Client.load_paginated_items_list(@auth, '/customers.json', Customer, options, limit)
    end
def customers(limit=0, firstName=nil, lastName=nil, email=nil)
      options = {}
      if firstName
        options[:firstName] = firstName
      end
      if lastName
        options[:lastName] = lastName
      end
      if email
        options[:email] = email
      end

      Client.load_paginated_items_list(@auth, '/customers.json', Customer, options, limit)
    end
List Customers
 http://developer.helpscout.net/help-desk-api/customers/list/

 Customers can be filtered on any combination of first name, last name, and
 email.

 Customers are returned by createdAt date, from newest to oldest.

 Request
  REST Method: GET
  URL: https://api.helpscout.net/v1/customers.json

  Parameters:
   Name           Type      Required  Default  Notes
   Name       Type    Required  Default
   firstName  String  No
   lastName   String  No
   email      String  No
   page       Int     No        1

 Response
  Name   Type
  items  Array  Collection of Customer objects.