tree 0e923fff54d1e2fd3b37aacff83eecf11f67a5a6
parent 8dfd91367fc8c70aaa96f83fe98c09f8dcfe50d8
author Davide Pesavento <davide.pesavento@lip6.fr> 1542859848 -0500
committer Davide Pesavento <davide.pesavento@lip6.fr> 1542859848 -0500

util: backport C++17 std::any and std::variant

The backported implementations are taken from Martin Moene's any-lite
(commit a2ee2e1cc4a3fcfe42ab44c46a65467b76b58f25) and variant-lite
(commit ff251b02253ff28db49bb20a79200514d8267d87).

The bundled copy of optional-lite is updated to commit
9a370efe62e084729a171a407b017aa58dc954c1.

Change-Id: I4afe117e357c82d51002f96b083aed0ec5eeda35