Add deferred indexing support

[supercid]

Is your feature request related to a problem? Please describe.

• We would need a way to defer the indexing when mass updates are done
• For example, Vaimo did change categories for 7000 products before Black Friday and it took over an hour to process the Nosto data Why?
• Speed up the indexing and not interfere too much in other processes running in Magento

Describe the solution you'd like

• We would need another table where to queue updated products (simply just a product id, perhaps only the parent product id)
• Custom cron job that would fetch product ids from the queue and run the actual indexing
• This could be used with the indexer or with product API updates in general

Describe alternatives you've considered A clear and concise description of any alternative solutions or features you've considered.

Additional context Add any other context or screenshots about the feature request here.

[supercid]

Closed in favor of #539 and #538