Properly decide terminal width on non-unix systems

[xypwn]

Pull Request Process

Before submitting a pull request

Be sure you have the latest code in hand. Pull the master branch

Be sure to make test and keep all test pass

Be sure to make tidy so your code style will keep the same

Be sure to make cover-report to see if any line not covered

Don't Rebase git history

General steps for completing this pull request

Checklist

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Ensure that your pull request has followed all the steps below:

• Code compilation
• All tests passing
• Extended the documentation, if applicable

Description

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stty isn't available on Windows. This patch uses golang.org/x/term instead to determine the actual terminal width. This makes it work on Windows without issues.

Proposed changes

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This improves the UX on Windows, or any other system where the "stty" command may not be available.

Types of changes

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• New feature
• Bugfix
• Improve
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[xypwn]

I accidentally created a previous PR from the wrong branch in my fork (#23). Sorry for duplicate PR.

[hellflame]

That's great, thanks for the contribution!