Building ethereum
set "GOPATH=C:\g\ethereum\go-ethereum-src"
set "Path=%USERPROFILE%\bin;%Path%"
setx GOPATH "%GOPATH%"
setx Path "%Path%"
mkdir src\github.com\ethereum
git clone https://github.com/ethereum/go-ethereum src\github.com\ethereum\go-ethereum
cd src\github.com\ethereum\go-ethereum
go get -u -v golang.org/x/net/context