clarify compilation information wrt the client

README.md

@@ -17,3 +17,9 @@ and here to install Qt: https://github.com/therecipe/qt
 - `cmd`: contains our executable programs
 - `cmd/count-client`: a gRPC client with a Qt ui
 - `cmd/count-server`: a gRPC server, no graphical ui
+
+### Compiling the client:
+
+Compiling the client is a bit tricky. The way I got this to work was to use MSYS2 and MinGW-64. I installed the pacman package `mingw-w64-x86_64-qt-creator`, which includes a 64-bit gcc. I was able to piece together the install process that worked for me based on the instructions found in the https://github.com/therecipe/qt README, [the MSYS2 wiki](https://sourceforge.net/p/msys2/wiki/MSYS2%20introduction/), and [the MSYS2 page of the Qt wiki](https://wiki.qt.io/MSYS2).
+
+_this has only been tested on Windows 10_