Summary:
We shove alias parameters onto the front of the arg list so if you make an alias like "qdiff" = "diff x y z" and then run "qdiff a b c", we end up with "diff x y z a b c". However, currently we reverse alias parameters, so you actually get "diff z y x a b c".
This is a problem for `arc alias bdiff -- diff --background 1`, which evaluates to `arc diff 1 --background` and fails.
Test Plan: Created a `bdiff` alias and ran it successfully.
Reviewers: vrana, btrahan
Reviewed By: btrahan
CC: aran
Differential Revision: https://secure.phabricator.com/D3196