Implement version selector install guides

[ys2843]

Description

fix #18833 and #18666
This PR includes the changes to create a comprehensive installation widget that covers all the versions.

Changes

• Bring back missing installation guide contents

Comments

• Preview: http://ec2-34-219-134-42.us-west-2.compute.amazonaws.com/get_started?

[mxnet-bot]

Hey @ys2843 , Thanks for submitting the PR
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[ys2843]

@mxnet-label-bot remove [pr-awaiting-review]

[ys2843]

@mxnet-bot run ci [unix-cpu, windows-gpu]

[mxnet-bot]

Jenkins CI successfully triggered : [unix-cpu, windows-gpu]

[leezu]

Thank you @ys2843. Let's remove the windows docker instructions, as they only exist in the codebase due to a symlink but are not supported and shouldn't be shown on the website.

I think the symlink would be removed as part of adding platform and version specific build from source instructions in #18666

[ChaiBapchya]

Thanks @leezu good catch!

[ys2843]

Thank you @ys2843. Let's remove the windows docker instructions, as they only exist in the codebase due to a symlink but are not supported and shouldn't be shown on the website.

I think the symlink would be removed as part of adding platform and version specific build from source instructions in #18666

@leezu Just to clarify, since we are going to have a unified installation widget that covers all versions. In which version we don't support windows/docker? Because if we still support them in previous versions, these symlink still need to be there. And we just hide windows/docker for some certain versions.