add contract diffs to contracts.go
add contract diffs to contracts.go

ericflo/Sia,rivine/rivine,NebulousLabs/Sia,mnsl/Sia,mnsl/Sia,rivine/rivine,mharkus/Sia,mtlynch/Sia,Mingling94/Sia,mtlynch/Sia,MrStrong/Sia,ChrisSchinnerl/Sia,ChrisSchinnerl/Sia,MrStrong/Sia,mharkus/Sia,cyrozap/Sia,johnathanhowell/Sia,ericflo/Sia,kustomzone/Sia,NebulousLabs/Sia