Update directory structure of test cases

[rockacola]

Description

Update directory structure of test cases

Motivation and Context

Originally the nodejs directory was created to separate from other type of usages such as through web browser, etc. This may not be relevant anymore.

How Has This Been Tested?

Types of changes:

• Bug fix (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 change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.