Add vscode to gitignore

[Kaytbode]

vscode directory includes a settings.json file for vscode. This
should not be added to version control as it is specific to vscode.

There are no side effects associated with this change.

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Proposed changes

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why we should accept this pull request. If it fixes a bug or resolves a feature
request, be sure to link to that issue.

The change is actually a chore. vscode directory includes a settings.json file for vscode
editor. The settings is particular to vscode users, and I feel it should not be included in version
control.

Types of changes

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• [x ] Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

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• [ x ] I have read the CONTRIBUTING doc
• [ x ] I agree to contribute my changes under the project's LICENSE
• [ x ] I have checked that the unit tests pass locally with my changes
• [ x ] I have checked the style of the new code (lint/pep).
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] I have added necessary documentation (if appropriate)

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[coveralls]

Coverage increased (+0.2%) to 73.594% when pulling 65e1606 on Kaytbode:modified-gitignore into f9a9a26 on coursera-dl:master.