Cache translations and nav menus

[szepe.viktor]

I've noticed caching translations and navigation menus HTML output makes WordPress load much faster. (Using persistent object cache)

I am experimenting with these two (an the_content() caching) in this repo
​https://github.com/szepeviktor/tiny-cache

Please consider caching these two in the core.
Thanks.

[swissspidy]

For caching menus there's already #36225.

[SergeyBiryukov]

And for translations there's #17128, #17268, and #32052 :)