title: Setting `GOPATH` for each vscode project
body: <p>Setting the <code>GOPATH</code> variable global as an enviroment variable works fine with Visual Studio Code.</p>
  
  <p>But setting a project specific variable globally doesn't seem very nice to me. Consider you have multiple <code>Go</code> projects, you would have to change this variable each time you, compile, debug, ... etc. a project.</p>
  
  <p>Is there a possibility to set the <code>GOPATH</code> variable as a project variable in Visual Studio Code? Ether in <code>settings.json</code> or <code>launch.json</code>?</p>