Include localized message files in the typescript npm package

[mhegazy]

In order to support microsoft/vscode#18634 (comment), we need to publish localized messages with the TS package.

[gcnew]

What will the process be for contributing changes that add or touch existing messages? Who will translate them?

[mhegazy]

We already have translated messages that are shipped as part of VS. I will need to figure out the process of getting these into the main TS npm package..