We'll use this to call the Windows ReplaceFile API for safe file
replacement when updating credentials.tf.json in "terraform login" and
"terraform logout".
This corrects a bug in the HCL 2 scanner where a $ or % symbol would cause
incorrect tokenization if appearing immediately before a " .
This also includes some updates to Go extension libraries that the HCL
update brings in. Some of these changes update to support Unicode 11, but
only when compiling with Go 1.13, so we won't see the effect of these
changes until we start building Terraform with Go 1.13.
Martin Atkins