Add Alpine Linux build

[maxirmx]

No description provided.

[ronaldtse]

Thanks @maxirmx ! Could you help squash some of the commits to make the history nicer (e.g. the "Alpine build n" commits, squash the "More cache tests"), and rebase/merge? Thanks!

[maxirmx]

@ronaldtse this commit includes a patch to Folly and a patch to Alpine build-base package.
Folly readme says "we aim to support macOS and Linux (on the latest Ubuntu LTS release or newer.)"
Does it make sense to place PRs ?

[ronaldtse]

@ronaldtse this commit includes a patch to Folly and a patch to Alpine build-base package.

Absolutely. Could you help send a PR (from a fork in the https://github.com/tamatebako organization) with the following signature:

This is a contribution from the [Tebako](https://github.com/tamatebako/tebako) project of [Ribose](https://github.com/riboseinc).

Thanks!