Improvements:
- The filemd5, filesha1, etc functions from Terraform v0.12 are backported primarily to allow writing modules that can work in both Terraform 0.11 and 0.12
- backend/remote: Retry calls when the remote backend responds with a server error
- backend/remote: Check for external updates while waiting for user input
Bug fixes:
- backend/remote: Fix "token too long" errors when streaming remote operation logs
- backend/remote: Use the can-queue-apply permission to detect if apply is allowed
- backend/remote: Exit with 1 when a remote run is canceled
- core: Use slashes in the module manifest to prevent Windows/Linux compatibility issues