Add the -V/--version option

The -V/--version option prints the nitrocli version to stdout and exits.
In the future, it should also print the used libnitrokey version, but as
the required function is only available with nitrokey 0.3.2 and as the
current interface does not reflect the latest change in version naming,
I skipped that in this patch.

nitrocli/CHANGELOG.md

@@ -1,3 +1,8 @@
+Unreleased
+----------
+- Added the `-V`/`--version` option to print the program's version
+
+
 0.2.3
 -----
 - Added the `storage hidden` subcommand for working with hidden volumes

nitrocli/doc/nitrocli.1

@@ -4,6 +4,7 @@ nitrocli \- access Nitrokey devices
 .SH SYNOPSIS
 .B nitrocli
 [\fB\-m\fR|\fB\-\-model pro\fR|\fBstorage\fR] \fR[\fB\-v\fR|\fB\-\-verbose\fR]
+[\fB\-V\fR|\fB\-\-version\fR]
 \fIcommand\fR
 [\fIarguments\fR]
 .SH DESCRIPTION
@@ -25,6 +26,9 @@ supplied multiple times. A single occurrence will show additional warnings.
 Commands sent to the device will be shown when supplied three times and full
 device communication is available with four occurrences. Supplying this option
 five times enables the highest verbosity.
+.TP
+\fB\-V\fR, \fB\-\-version\fR
+Print the nitrocli version and exit.
 .SH COMMANDS
 .SS General
 .TP

nitrocli/src/args.rs

@@ -844,6 +844,11 @@ fn parse_arguments<'io, 'ctx: 'io>(
  let cmd_help = cmd_help!(command);
  let mut subargs = vec![];
  let mut parser = argparse::ArgumentParser::new();
+ parser.add_option(
+ &["-V", "--version"],
+ argparse::Print(format!("nitrocli {}", env!("CARGO_PKG_VERSION"))),
+ "Print version information and exit",
+ );
  let _ = parser.refer(&mut verbosity).add_option(
  &["-v", "--verbose"],
  argparse::IncrBy::<u64>(1),