add instructions using go env -w

SettingGOPATH.md

@@ -3,15 +3,25 @@
 The `GOPATH` environment variable specifies the location of your workspace. If no `GOPATH` is set, it is assumed to be `$HOME/go` on Unix systems and `%USERPROFILE%\go` on Windows. If you want to use a custom location as your workspace, you can set the `GOPATH` environment variable. This page explains how to set this variable on various platforms.
 
 - [Unix systems](#unix-systems)
+  * [Go 1.13](#go-113)
   * [Bash](#bash)
   * [Zsh](#zsh)
   * [fish](#fish)
 - [Windows](#windows)
+  * [Go 1.13](#go-113-command-line)
+  * [Windows 10 (GUI)](#windows-10-gui)
+  * [Windows 10 (command line)](#windows-10-command-line)
 
 # Unix systems
 
 `GOPATH` can be any directory on your system. In Unix examples, we will set it to `$HOME/go` (the default since Go 1.8). Note that `GOPATH` must not be the same path as your Go installation. Another common setup is to set `GOPATH=$HOME`.
 
+## Go 1.13
+
+```bash
+go env -w GOPATH=$HOME/go
+```
+
 ## Bash
 
 Edit your `~/.bash_profile` to add the following line:
@@ -62,13 +72,17 @@ __NOTE:__ `GOPATH` must not be the same path as your Go installation.
 * Type `C:\go-work` into the "Variable value" field.
 * Click OK.
 
-## Windows 10
+## Go 1.13 (command line)
+* Open a command prompt (`Win` + `r` then type `cmd`) or a powershell window (`Win` + `i`).
+* Type `go env -w GOPATH=c:\go-work`.
+
+## Windows 10 (GUI)
 There is a faster way to edit `Environment Variables` via search:
 * Left click on "Search" and type `env` or `environment`.
 * Select "Edit environment variables for your account".
 * ... and follow steps above.
 
-## Windows 10 (cli version)
-* Open a command prompt (windows-key + r then type "cmd") or a powershell window (windows-key + i)
-* Type `setx GOPATH %USERPROFILE%\go` (this will set the `GOPATH` to your `[home folder]\go` e.g. `C:\Users\yourusername\go`
-* Close the command or powershell window (the environment variable is only available for new command or powershell windows, not for the current window).
+## Windows 10 (command line)
+* Open a command prompt (`Win` + `r` then type `cmd`) or a powershell window (`Win` + `i`).
+* Type `setx GOPATH %USERPROFILE%\go`. (This will set the `GOPATH` to your `[home folder]\go`, such as `C:\Users\yourusername\go`.)
+* Close the command or powershell window. (The environment variable is only available for new command or powershell windows, not for the current window.)