experimental feature application reset, better primary scan, equalize stderr output

- add new function to send application reset incl. subcode
- fix typo in comment
- add new program to test experimental feature application reset
- add mbus-tcp-application-reset to build process
- print all errors on stderr in all binaries
- add new parameter to specify retries for mbus-serial-scan and mbus-tcp-scan
- make primary scan to retransmit SND_NKE in case of timeout so it's more reliable but also slowlier
- keep default behaviour, no retransmission
- equalize mbus-serial-scan and mbus-tcp-scan
- update man page