Auto merge of #677 - edunham:4new, r=larsbergstrom
Auto merge of #677 - edunham:4new, r=larsbergstrom

Add 4/5 of the new macs

See https://github.com/servo/saltfs/issues/674#issuecomment-303591568.

Test that the 4 completed new builders are actually working, and free up a bit of capacity, while I finish up with mac9.

Also format these lines to have less icky diffs as we add and remove others.

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servo/saltfs,servo/saltfs