Auto merge of #3630 - alexcrichton:empty-version, r=alexcrichton
authorbors <bors@rust-lang.org>
Wed, 1 Feb 2017 21:03:21 +0000 (21:03 +0000)
committerbors <bors@rust-lang.org>
Wed, 1 Feb 2017 21:03:21 +0000 (21:03 +0000)
Fix empty 'version' file

This teaches the makefiles to construct the version string again so
it can be emitted to the 'version' file for packaging.

Fixes failing nightly builds.


Trivial merge