listCustomers()
This application is used to get list of customers belonged to customer.
Implementation details
This function supports trusted mode in which case i_wholesaler (integer) parameter should be supplied.
Parameters:
- offset - skip fist offset records. Integer. Optional.
 - limit - return only limit records. Integer. Optional.
 
Returns:
- result - OK means that query was successful. String.
 - 
customers - an array containing structures:
- i_customer - Integer.
 - name - String.
 - web_login - String.
 - description - String.
 - balance - Double.
 - credit_limit - Double.
 - base_currency - String.
 
 - XMLRPC fault in case of any error.