API:Add Credit

 $postfields["action"] = "addcredit";
 $postfields["clientid"] = "1";
 $postfields["description"] = "Adding funds via custom module";
 $postfields["amount"] = "40.00";

 $command = "addcredit";
 $adminuser = "admin";
 $values["clientid"] = "1";
 $values["description"] = "Adding funds via custom module";
 $values["amount"] = "40.00";
 
 $results = localAPI($command,$values,$adminuser);

 result = success 
 newbalance = xx.xx - the total credit balance the client now has

result=error&message=Client ID Not Found #Given Client ID is not found in the database.