This example demonstrates how custom Modbus functions (vendor specific)
can be added for the Modbus/TCP protocol.

A flow computer offers several functions using Modbus function code 71
subfunction 1 to 5. These custom functions are added through the class
CustomFunctions.pas: 

- Get Hourly Log Records
- Get Daily Log Records
- Prepare Alarm/Event Log
- Read Alarm/Event Log Record
- Acknowledge Alarm/Event Log Record

The files CustomFunctionsUnit.pas contains the GUI logic, 
CustomFunctionsForm.pas the GUI form and CustomFunctionsDemo.dpr is the 
main program.

