Adds inclusive naming

[harshavamsi]

Description

• Renames master to cluster_manager
• Adds cluster_manager_timeout while deprecating master_timeout
• Adds a new cat/cluster_manager API while deprecating cat/master

Issues Resolved

Closes #72

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[saratvemulapalli]

@tlfeng could you take a stab at this review?

[dblock]

Does this work equally well against multiple major versions of OpenSearch 1.x, 2.x and 3.x? If I am using an older version against OpenSearch 2.x can I upgrade to this client without rewriting any code? Then can I just start calling the new APIs to remove deprecations?

[dblock]

@Yury-Fridlyand you did this recently for .NET client - care to take a look at this?

[Yury-Fridlyand]

I'm noob in ruby, but I'll do my best.
My first finding so far:

opensearch-ruby/opensearch-api/lib/opensearch/api/utils.rb

Lines 99 to 107 in bc935d0

	# OpenSearch::API::Utils.__bulkify [
	# { :index => { :_index => 'myindexA', :_type => 'mytype', :_id => '1', :data => { :title => 'Test' } } },
	# { :update => { :_index => 'myindexB', :_type => 'mytype', :_id => '2', :data => { :doc => { :title => 'Update' } } } }
	# ]
	#
	# # => {"index":{"_index":"myindexA","_type":"mytype","_id":"1"}}
	# # => {"title":"Test"}
	# # => {"update":{"_index":"myindexB","_type":"mytype","_id":"2"}}
	# # => {"doc":{"title":"Update"}}

AFAIK, _type support was remoted in OpenSearch, see opensearch-project/OpenSearch#1940.
Please, check this comment, and it is outdated, update it and let me know. There are few more comments like this, perhaps they should be updated too.

[dblock]

Want to make sure we're working on integration tests that run against both OpenSearch 1.x and 2.x.

Fix CI? Looks like the code needs to be server-version aware.

[harshavamsi]

Does this work equally well against multiple major versions of OpenSearch 1.x, 2.x and 3.x? If I am using an older version against OpenSearch 2.x can I upgrade to this client without rewriting any code? Then can I just start calling the new APIs to remove deprecations?

Yes, we've only deprecated the master nomenclature without removing them and added new endpoints for cluster_manager.

[wbeckler]

@nhtruong would you be able to review this? If you review, I'll approve.

[VachaShah]

@harshavamsi Can you rebase with main? This would need a CHANGELOG after the rebase.