message: Add note re gcc 8.2.1
diff: @@ -80,7 +80,9 @@ __Note__: make sure these programs are not only installed but also added to your
  Some instructions in this document may assume that you're using a bash command prompt, such as the Windows 10 built-in bash or [Git](https://git-scm.com/download/win) bash.
  -* [ARM compiler](https://developer.arm.com/open-source/gnu-toolchain/gnu-rm/downloads) __Note__: After installing, create an environment variable named `ARM_GCC_ROOT` whose value is the path you installed to. e.g. `C:\Program Files (x86)\GNU Tools Arm Embedded\7 2018-q2-update`. This variable is used to locate include files for the c/c++ Visual Studio Code extension.
  +* [ARM compiler](https://developer.arm.com/open-source/gnu-toolchain/gnu-rm/downloads)
  + * __Note 1__: After installing, create an environment variable named `ARM_GCC_ROOT` whose value is the path you installed to. e.g. `C:\Program Files (x86)\GNU Tools Arm Embedded\7 2018-q2-update`. This variable is used to locate include files for the c/c++ Visual Studio Code extension.
  + * __Note 2__: 8-2018-q4-major seems to have a bug on Windows. Please use 7-2018-q2-update.
  * [Tup](http://gittup.org/tup/index.html)
  * [Make for Windows](http://gnuwin32.sourceforge.net/packages/make.htm)
  * [OpenOCD](http://gnuarmeclipse.github.io/openocd/install/). Also follow the instructions on the ST-LINK/V2 drivers.
  