[Ruby] Enhance Faraday middleware support

[ykitamura-mdsol]

Thanks to @johngallagher Faraday middlewares are configurable now:

• [REQ] [RUBY] [FARADAY] Allow middleware to be configured #10495

In this PR, I'd like to enhance the Faraday middleware support to be able to call the methods to push onto the various positions in the stack (insert, insert_before, insert_after, swap, and delete) and also to be able to pass a block to the methods.

Usage

PetstoreAPI.configure do |config|
  config.set_faraday_middleware(:request, :retry, max: 3, methods: [:get, :post], retry_statuses: [503])
  config.set_faraday_middleware(:response, :logger, nil, { bodies: true, log_level: :debug })
  config.set_faraday_middleware(:use, Faraday::HttpCache, store: Rails.cache, shared_cache: false)
  config.set_faraday_middleware(:insert, 0, FaradayMiddleware::FollowRedirects, { standards_compliant: true, limit: 1 })
  config.set_faraday_middleware(:swap, 0, Faraday::Response::Logger) })
  config.set_faraday_middleware(:delete, Faraday::Multipart::Middleware)
  :

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@wing328

[wing328]

@ykitamura-mdsol thanks for the PR.

cc @cliffano (2017/07) @zlx (2017/09) @autopp (2019/02)