Added command line flags for help and version

[tinywombat765]

I added help and version cli flags

Signed-off-by: zethra benaagoldberg@gmail.com

[dani-garcia]

Looks good to me, I assume this auto generates the --help flag by itself?
I'd change the short flag of --version to a lowercase v, which I think is the most common option.

[jjlin]

-V is pretty common too, especially when -v is taken for verbose.

[tinywombat765]

@dani-garcia Yes, help is auto generated. As far as the version flag, I was thinking along the same lines as @jjlin but I can change it if you want.

[dani-garcia]

Well I don't think we are going to be supporting a verbose flag when we have explicit log level options, so I think it's better to keep them all lowercase for the sake of consistency

[mqus]

Regarding the version, wouldn't it be possible to use env!("CARGO_PKG_VERSION") as a backup, provided that the version in cargo.toml is kept up-to-date? (It's currently still at 1.0.0 though)

[dani-garcia]

It's an option, yeah, but it's another thing to keep track of before a release and if I ever forget to do it the release will end up with an incorrect version, which is worse than no version at all, I'd say.

[dani-garcia]

thanks, @zethra!