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[rebornix]

Yay! We love PRs! 🎊

Please include a description of your change & check your PR against this list, thanks:

• Commit message has a short title & issue references
• Commits are squashed
• It builds and tests pass (e.g gulp tslint)

Fix #214. Since currently we don't have VS Code Screen Line support, we simply use 20 as the half window size, but users can configure vim.scroll to override this setting the same as Vim.

[johnfn]

hype

[sachin21]

Thank you so much for implement!