Build server archive

I've created some Thor tasks in the build_server_archive.thor that will create a tarball of the files needed by the lab web server app, lab-interactive-management.
The tar file name includes the short commit hash for repo's HEAD commit.

To create and upload this tar to S3 from the root of the lab repo:
thor build_server_achive:upload_tarball

This will return a URL to access this tar file.