usually pointing to proper compilator for respective platform.

coupler1 and coupler2 are subscribed over keep-alive network implementation
over Pub/Sub to coupler3.
Coupler3 is sending heart_beats every 10ms and if not heart_beat is received
by coupler1,2 within 50ms they both go to "safe" mode.

Do not subscribe to Pub/Sub in case we actually do not explicitly have configured so. Printouts for better traceability.

See merge request !22

Remove traces of compiled forms of the project and add an archive of it (which will itself be compiled at slapos instance step.)

This reverts commit 837b1b46.

This reverts commit bc0c17eb.

See merge request !20

The unit tests for the functions have been added.

modified:   coupler/opc-ua-server/mod_io_i2c.h
        new file:   tests/unit_test/Makefile
        new file:   tests/unit_test/test_common.c
        new file:   tests/unit_test/test_modio_i2c.c
        new file:   tests/unit_test/unit_test.md

Test: Program is tested

keep alive message. THis is not a sane value (1s) but is a temporary workaround
around real problem which is that in this implementation coupler's subscribe
implementation can not cope with flood of subscribed to it UDP diagrams.
Real solution to reach high avialability is to make coupler's UDP handling
use multithreading and signifficantly speed up UDP handling in Subscribe part.