Saves full dataset on disk, uses go-etherium code.
go get github.com/kkibria/ethdag
will install the package and dependency, go-etherium. Copy the file sizes.go from the ethdag/ethash directory to the ethash directory of the go-etherium source tree. This will expose the cacheSize and datasetSize functions we need.
Running go install will compile and install the executable in $GOPATH/bin directory.