add python 3 tests to most shell scripts

hardware/sensehat/package.json

@@ -1,6 +1,6 @@
 {
     "name"          : "node-red-node-pi-sense-hat",
-    "version"       : "0.1.0",
+    "version"       : "0.1.1",
     "description"   : "A Node-RED node to interact with a Raspberry Pi Sense HAT",
     "repository" : {
         "type":"git",

hardware/sensehat/sensehat

@@ -1,5 +1,9 @@
 #!/bin/bash
 
+python_cmd='python3'
+# Fallback to Python 2, if Python 3 is not available
+command -v python3 > /dev/null || python_cmd=`python`
+
 BASEDIR=$(dirname $0)
 
 ID=$(id -u)
@@ -11,4 +15,4 @@ then
    SUDO=""
 fi
 
-$SUDO python -u $BASEDIR/sensehat.py $@
+$SUDO $python_cmd -u $BASEDIR/sensehat.py $@