Add an entry for Gogland (#775)

Documentation/EditorIntegration.md

 The following editor plugins for delve are available:
 
 * [Golang Plugin for IntelliJ IDEA](https://github.com/go-lang-plugin-org/go-lang-idea-plugin)
+* [JetBrains Gogland](https://www.jetbrains.com/go) - "early access" builds so far
 * [Go for Visual Studio Code](https://github.com/Microsoft/vscode-go)
 * [Emacs plugin](https://github.com/benma/go-dlv.el/)
 * [LiteIDE](https://github.com/visualfc/liteide)