MOBILE-4362 lang: Improve error message

scripts/lang_functions.sh

@@ -14,6 +14,12 @@ function get_app_version {
         return
     fi
 
+    if ! command -v jq &> /dev/null
+    then
+        echo "You need to install the jq program in order to run this command"
+        exit 1
+    fi
+
     APP_VERSION=$(jq -r '.versionname' ../moodle.config.json| cut -d. -f1-2)
     if [ ! -z "$APP_VERSION" ]; then
         export LANGVERSION=$APP_VERSION