Create home for Rushstack VSCode Extension w/ simple Rush CD Command

[TheLarkInn]

Summary

There has been many talks about creating integrations with vscode for Rushstack and its collection of tools/utilities. This PR introduces a new home under apps for our VS Code Extension to Live

Details

Included in this VS Code Extension is a simple command called "Rush CD" which allows a user to type a command into the command prompt of VS Code => Type Rush CD => and then choose a RushConfigurationProject they would like to focus into (by opening that projects package.json).

Searching for Command:

Using Command:

Text filtering based off of package.json description, path, and rush project name:

Opening package.json of selected project:

If user has no Rush.json in workspace:

In addition Debugger support for the extension has been included in our launch.json configuration, and therefore should make testing the extension easier.

Unknowns

• Am I missing any setup packages
• Are we happy with the naming conventions and folder structure of the extension
• Does @dmichon-msft 's extension work also need to be integrated? Should I wait on his? (The command is super portable so no worries either way).

How it was tested

Test's need to be added. There is a test launch.json action, however I have not integrated it with Jest yet. This will have to be a TODO.

Related: #3157 #vscode

[TheLarkInn]

Closing for #3162 and will review that instead. Will keep my branch running.