因为墙的问题，碰到golang.org/x包无法获得的解决方案：
git clone https://github.com/golang/net.git %GOPATH%/src/github.com/golang/net
git clone https://github.com/golang/sys.git %GOPATH%/src/github.com/golang/sys
git clone https://github.com/golang/tools.git %GOPATH%/src/github.com/golang/tools
ln -s %GOPATH%/src/github.com/golang/ %GOPATH%/src/golang.org/x
go get -v sourcegraph.com/sqs/goreturns
go get -u -v github.com/nsf/gocode
go get -u -v github.com/rogpeppe/godef
go get -u -v github.com/golang/lint/golint
go get -u -v github.com/lukehoban/go-find-references
go get -u -v github.com/lukehoban/go-outline
go get -u -v sourcegraph.com/sqs/goreturns
go get -u -v golang.org/x/tools/cmd/gorename
go get -u -v github.com/tpng/gopkgs
go get -u -v github.com/newhook/go-symbols
