Update the provider schema and introduce the new Scaleway configuration

[QuentinBrosse]

This issue is part of the migration plan to the v2 of this provider. (https://github.com/terraform-providers/terraform-provider-scaleway/issues/140)

The goal of this issue is to update the provider schema in anticipation of the new breaking change schema who will be introduced in the next major version (v2.0.0).

This issue is totally backward compatible. Moreover, it introduces some deprecations (more info below).

More info:

• Scaleway SDK Go config
• Provider configuration doc
• Migration guide

The new provider schema

Deprecate token

This field is now deprecated in favor of the new secret_key. Therefore, this field is now optional in order to allow users to switch to the new secret_key. This field will be removed in the next major version (v2.0.0).

Deprecate organization

This field is now deprecated in favor of the new organization_id. Therefore, this field is now optional in order to allow users to switch to the new organization_id. This field will be removed in the next major version (v2.0.0).

Add secret_key

This is the new way to set the Scaleway API secret key. This field is optional to allow users to set this value via the deprecated token attribute during the transition.

The default value is found with the new scwconfig (more info).

Add project_id

This field is optional to allow users to set this value via the deprecated organization attribute during the transition.

The default value is found with the new scwconfig (more info).

Add zone

To support the new Scaleway locality policy we added a new zone field.

The default value is found with the new scwconfig (more info).

Change access_key

Currently, the default value is SCALEWAY_ACCESS_KEY. If this default value is empty, we are now trying to find it with the new scwconfig (more info).

Change region

Currently, the default value is SCALEWAY_REGION . If this default value is empty, we are now trying to find it with the new scwconfig (more info). In the worst case, the ultimate default value - par1 - is conserved.

In existing resources, you can't override this value. In the next few days, a new implementation of these resources will be released. They will provide a region field in order to override this value. Therefore, you can consider this field as the default region for the new resources.