add block mining success message
add block mining success message

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