This reverts commit bb0fb7f6.

increase it heart beats which itself will cause
dependent couplers to detect that a coupler is DOWN.

See merge request !64

See merge request !63

See merge request !62

See merge request !61

This way the PLC program can handle the exception accordingly
rather that simply hide it as till now.

Update CLI arguments' descriptions.

See merge request !60

See merge request !59

Add DTS file for STM32MP1 based olinuxino-lime board.

(for testing purposes).