tweak constants, add defrag transaction size logging
tweak constants, add defrag transaction size logging

NebulousLabs/Sia,mnsl/Sia,mharkus/Sia,ChrisSchinnerl/Sia,mtlynch/Sia,mnsl/Sia,ericflo/Sia,MrStrong/Sia,mharkus/Sia,mtlynch/Sia,ChrisSchinnerl/Sia,NebulousLabs/Sia,ericflo/Sia,MrStrong/Sia