Revert "Build all archs for compatibility with universal targets"
Revert "Build all archs for compatibility with universal targets"

This reverts commit 8c02bd445601a954db2244cd3d34de5d3493db6f.

gudatcomputers/PivotalCoreKit,pivotaltracker/PivotalCoreKit,joemasilotti/PivotalCoreKit,idoru/PivotalCoreKit,joemasilotti/PivotalCoreKit,idoru/PivotalCoreKit,pivotal/PivotalCoreKit,gudatcomputers/PivotalCoreKit,briancroom/PivotalCoreKit,mjstallard/PivotalCoreKit,jfuchs/PivotalCoreKit,jfuchs/PivotalCoreKit