[Feat]: Add a note in Marker's CLI if there is a newer version available

[xFrednet]

Summary

I would like Marker's CLI to have a small check if a newer version is available. If this is a case, a small note should be added, letting the user know that they can update Marker, if they'd like to.

I'm thinking of something simple like this:

$ cargo marker
        Info Marker v0.3 is avilable

      Marker compiling lints
    Updating crates.io index
[...]

This should just be an info and nothing more severe, as CIs should continue to work uninterrupted.

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We can use Cargo's search command to check for the newest version:

cargo search cargo_marker --limit 1

We just need to parse the output and compare it to our own version.

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We would also want a CLI flag to disable this behavior. Maybe --no-update-check or something similar.