2020-04-03	v0.3.1 fixed complicated interrupting by ctrl-c
2019-03-26	v0.3.0 add support for time/date handling
2019-03-16	v0.2.3 fixed serial port setup to work on Mac
2019-03-09	v0.2.2 remove unnecessary waiting after last block
2019-03-02	versions before this date was unreleased