This adds the new `required_plugins` block to be nested under the packer block.
Example:
```hcl
packer {
required_plugins {
aws = {
version = ">= 2.7.0"
source = "azr/aws"
}
azure = ">= 2.7.0"
}
}
```
For example on darwin_amd64 Packer will install those under :
* "${PACKER_HOME_DIR}/plugin/github.com/azr/amazon/packer-plugin-amazon_2.7.0_x5.0_darwin_amd64"
* "${PACKER_HOME_DIR}/plugin/github.com/hashicorp/azure/packer-plugin-azure_2.7.0_x5.0_darwin_amd64_x5"
+ docs
+ tests
* hcl2template/addrs.ParseRef will parse a reference and tell for example if we
are referring to a variable and its name, for now it can only do that and in
the future it improved when we need to most of it is from the TF code. This
is used to tell wether a variable vas referenced in a variable validation
condition; for now.
* Added Validations blocks to the hcl2 Variable struct and code to
parse/validate that.
Adrien Delorme
Adrien Delorme