add build/var_test.go
add build/var_test.go

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