Dependency scraper

Created by: dbluhm

This PR adds a maven plugin that can be to retrieve files from dependencies and copy them to another location in the current project. This is primarily intended for use in Vaadin projects that use Data Elements from dependencies and being able to pull TypeScript representations of those data elements and other auto-generated TypeScript classes into the projects frontend sources.

This PR formerly included basic TypeScript generation but I removed it with the intent of keeping the change set limited for this PR.