Create functions to help securely store and retrieve user credentials

[ih]

Create JSL functions to interact with Keychain on mac, Credential Store on Windows, and the Secret Service API on Linux.  This could be very similar to the open source keyring R package.

This would provide a better solution for this post: save passwords securely  and the script here: Set and get credentials in the Credential Manager via PowerShell on Windows

[Ryan_Gilmore]

We are archiving this request. If this is still important please comment with additional details and we will reopen. Thank you!