DO NOT MERGE YET

Intel clang fix
Reproduced the clang bug with the following setup:
CentOS 6
clang 3.4 compiled with gcc 4.8.2
Boost 1.56.0
Figured out the error and sent a pull request (
I am actually surprised we have not encountered this error before.

This branch contains Joel's changes (https://github.com/broadinstitute/gamgee/pull/301) and my fix. Perhaps I should move my fix to a separate commit (distinct from Joel's commits)?