Compared to Terraform, Packer was lacking a capability to encode/decode
strings to/from base64-encoded text encoded with another encoding.
This could be problematic in some cases, mainly when working with
Windows, as most of the OS uses UTF-16LE as its standard encoding for
many operations.
Therefore, we take a page from Terraform here, and add those functions
to what Packer supports in an HCL2 context.
Lucas Bajolet
accbe97e1e