auto merge of #631 : alexcrichton/cargo/issue-514, r=brson
authorbors <bors@rust-lang.org>
Thu, 2 Oct 2014 19:13:13 +0000 (19:13 +0000)
committerbors <bors@rust-lang.org>
Thu, 2 Oct 2014 19:13:13 +0000 (19:13 +0000)
If the host system had $HOME/.cargo/config which configured a user name/email
then this test would fail because those would be prioritized over $USER.

Closes #514


Trivial merge