This function corresponds to terraform.NewInterpolatedVariable, but built
with HCL2 primitives. It accepts a hcl.Traversal, which is what is
returned from the HCL2 API functions to find which variables are
referenced in a given expression.
This package is intended to contain all the functionality for parsing,
representing, and formatting addresses of objects within Terraform.
It will eventually subsume the responsibilities of both the
InterpolatedVariable and ResourceAddress types in the "terraform" package,
but for the moment is just a set of types for representing these things,
lacking any way to parse or format them. The remaining functionality
will follow in subsequent commits.
Martin Atkins