doc: fix issues related to page scrolling
Checklist
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tests and code linting passes -
the commit message follows commit guidelines
Description of change
Moved the sidebar to a fixed position and moved the positioning of the main content to the page's body, which results in back/forward navigation through hash links and search highlight working again.
Added a script to prevent the main column from unintentional scrolling when the sidebar is scrolled outside its boundaries.
Fixes: https://github.com/nodejs/node/issues/6637 Based on: https://github.com/nodejs/node/pull/5716