[smsgate] add `DeviceID` field to the output

[smsgate] add priority param to send command

[ca] add private server certificate generation support

[docs] inlude short info about `smsgate-ca` tool

[actions] add linter

[messages] add `simNumber` flag alias

[docs] restructure Usage section

[build] add Docker release

[build] add Docker release

[ci] fix project name