This PR allows you to specify environment variables when using the shell helper and hooks. This will be useful in a number of ways, but the main use case right now is to be able to specify a custom TERRAGRUNT_SOURCE environment variable so that as we are generating a project, Terragrunt uses the local copy of infrastructure-modules rather than trying to download something from Git that has not yet been committed/published.
This PR allows you to specify environment variables when using the shell helper and hooks. This will be useful in a number of ways, but the main use case right now is to be able to specify a custom
TERRAGRUNT_SOURCE
environment variable so that as we are generating a project, Terragrunt uses the local copy of infrastructure-modules rather than trying to download something from Git that has not yet been committed/published.