ec_deployment: add support for data tiers

[marclop]

Description

I've split the pull request in individual commits which should make it
easier to review.

Adds support for node_roles and automatic migration from node_type_*
to node_roles. I will note a few things to make it easier to break
down all of these changes.

f972aa8:
Adds node_roles support by updating the SDK to the latest available
version, this makes the deployment template not work out of the box and
instead our client has to choose whether to use the node_type object
or the node_roles array.
Stack versions >= 7.10.0 can and should use node_roles since that
allows users to leverage the cold tier and autoscaling in the future
as well.
With the introduction of the "id" field, the topology elements needn't
use instance_configuration_id as the unique field, instead, id is
that unique field value.
The instance_configuration_id has been set as computed only and
cannot be set by the user anymore. For now, this change is present on
the Elasticsearch topology only, in the future, as other applications
might also auto scale, the API will change accordingly.
Last, it validates that a set topology element has a size > 0, otherwise
an error will be thrown.

99dfe21:
Another somewhat breaking change is the removal of the version computed
property in the Elasticsearch object. This field is completely redundant
and should not be used, instead the global version declares the version
for all of the deployment's applications. Since we're removing a field
from the schema and previous versions of the provider have saved it in
the state, we're adding a StateUpgradeFunc and bumping the current
schema version to 1. The schema upgrade function will only be run when
the saved state version is 0 and will only run once, then the state
schema version will be bumped to 1.

The rest of commits are updates to the tests, fixtures, documentation
and example files.

Related Issues

Closes #212

How Has This Been Tested?

Thoroughly unit and acceptance tested, additionally I've tested the same scenarios as the acceptance tests manually.

Types of Changes

• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation

[alaudazzi]

Left a few editing suggestions. LGTM for the documentation part.

[karencfv]

This is looking great @marclop 🎉 ! Just wondering if this PR should include an update to the ec_deployment data source as well 🤔 shouldn't be too big of a change I think? Otherwise I guess that should be tackled as a follow up

[karencfv]

Suggested change

	// esIC is no longer needed
	// esIC is no longer needed after the implementation of node roles

[karencfv]

Should we check that the correct node roles are set in this and all tests?

[marclop]

I thought about it, but node_roles are likely to evolve over time, if we're too strict in our assertions we'll end up having a lot of maintenance overhead, so I've opted to at least for now check this lightly rather than assert all the node roles for all topology elements.

[marclop]

@karencfv I'll add the datasource schema change as well.

[karencfv]

Thanks for adding this to the data source as well!

[marclop]

Tests actually passed, the post destroy tracking is what returned an error, so we're good to merge.