use auto& for histories
authorJoost VandeVondele <Joost.VandeVondele@gmail.com>
Sun, 28 May 2017 07:58:52 +0000 (09:58 +0200)
committerJoona Kiiski <joona@zoox.com>
Tue, 6 Jun 2017 16:56:13 +0000 (09:56 -0700)
commit1781439fc2bfb12f8a4e89b2a75fdeac6cd58672
treeff2b021af2d771cd82cec106131ba7579d0b8c76
parentecd3218b6b24bb54509dbe6e9b24517b7df7390d
use auto& for histories

No functional change.

Closes #1113
src/movepick.h