Change the way Project#previous_builds is calculated
Change the way Project#previous_builds is calculated

Probably a performance gain, but it doesn't matter -- it should save us
from count/size weirdness =)

factorylabs/integrity,faradayio/ci1,faradayio/ci1,integrity/integrity,factorylabs/integrity,dkastner/prism_ci,integrity/integrity,p/integrity,erik-escobedo/integrity,forresty/integrity,erik-escobedo/integrity,p/integrity,integrity/integrity,forresty/integrity