Add cargo install prerequisite instructions for Linux

[GuillaumeBailey]

Fixes: #478

[shssoichiro]

Is this last step actually needed? (I'm on Arch which just has everything available from the package manager, so I"m asking as a non-Ubuntu user.)

Also probably worth noting that cargo install will install the package to ~/.cargo/bin by default, so users may want to add that to their PATH.

[master-of-zen]

I just was trying that on ubuntu 20.04 instance and there is no libzimg-dev package

[GuillaumeBailey]

Also relevant: https://www.reddit.com/r/AV1/comments/rd5loo/guide_how_to_compile_av1an_on_ubuntu_2104/ I did test my eventual build and found that it segfaults due to vapoursynth. My documentation PR is therefore incomplete. Get Outlook for Android<https://aka.ms/AAb9ysg>

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________________________________ From: Zen ***@***.***> Sent: Wednesday, January 5, 2022 5:32:08 AM To: master-of-zen/Av1an ***@***.***> Cc: Guillaume Bailey ***@***.***>; Author ***@***.***> Subject: Re: [master-of-zen/Av1an] Add cargo install prerequisite instructions for Linux (PR #479) I just was trying that on ubuntu 20.04 instance and there is no libzimg-dev package — Reply to this email directly, view it on GitHub<#479 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/AAKQIUBQHJTOZZ2YPIXZH6TUURB5RANCNFSM5K7ADLPQ>. Triage notifications on the go with GitHub Mobile for iOS<https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675> or Android<https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub>. You are receiving this because you authored the thread.Message ID: ***@***.***>