Allow selection of driver version and set 14ab2ff as current default

README.md

@@ -258,6 +258,7 @@ A default `config.json.example` file is included for reference. Copy this file t
 "pregame_weather"                Bool    If enabled, will display the weather for the game's location on the pregame screen.
 "debug"                          Bool    Game and other debug data is written to your console.
 "demo_date"                      String  A date in the format YYYY-MM-DD from which to pull data to demonstrate the scoreboard. A value of `false` will disable demo mode.
+"driver_version"                 String  A branch name or commit SHA for the installed rpi-rgb-led-matrix library. Falls back to "master" if not present.
 ```
 
 ### Delaying Board Update

config.json.example

@@ -48,5 +48,6 @@
 	"pregame_weather": true,
 	"scrolling_speed": 2,
 	"debug": false,
-	"demo_date": false
+	"demo_date": false,
+	"driver_version": "14ab2ff"
 }

install.sh

@@ -134,6 +134,8 @@ if [ "$SKIP_MATRIX" = false ]; then
     cd submodules
     git clone https://github.com/hzeller/rpi-rgb-led-matrix.git matrix
     cd matrix
+    # Checkout the branch or commit specified in config.json for rpi-rgb-led-matrix
+    git checkout $(jq -re '.driver_version // "master"' ../../config.json)
     git pull
     make build-python PYTHON="$PYTHON"
     sudo make install-python PYTHON="$PYTHON"