More enforcement on installation Gazebo 9

It exits with 255 somehow

scripts/install_software.sh

@@ -32,7 +32,7 @@ rosdep update
 # FIXME: python2 dependencies?
 echo "--- Downloading PX4 and installing its dependencies"
 
-# v1.11.1, TODO: update to v1.12
+# v1.11.1, TODO: update to v1.12, remove Gazebo downgrade
 #git clone --recursive -b v1.11.1-clover https://github.com/CopterExpress/Firmware ${HOME}/Firmware
 ## PX4 v1.11.1 script will happily run sudo by itself
 #${HOME}/Firmware/Tools/setup/ubuntu.sh
@@ -112,6 +112,8 @@ source /opt/ros/noetic/setup.bash
 cd ${HOME}/catkin_ws && catkin_make
 echo "source ${HOME}/catkin_ws/devel/setup.bash" >> ~/.bashrc
 
+sudo -E sh -c 'apt-get update; apt-get install -y gazebo9' # downgrade Gazebo to 9 to make PX4 v1.10.1 work
+
 echo "--- Installing npm"
 cd ${HOME}
 NODE_VERSION=v10.15.0 # GitBook won't install on newer version
@@ -166,3 +168,39 @@ chmod a+x ${HOME}/Desktop/*
 
 echo "--- Cleaning up"
 sudo -E sh -c 'apt-get -y autoremove; apt-get -y autoclean; apt-get -y clean; fstrim -v /'
+
+echo "--- Validating"
+# python --version # python-is-python3
+python2 --version
+python3 --version
+# ipython --version
+ipython3 --version
+gazebo --version || true # FIXME: Gazebo exist with 255 on --version somehow
+node -v
+npm -v
+byobu --version
+git --version
+vim --version
+pip --version
+pip3 --version
+monkey --version
+systemctl --version
+
+source $HOME/catkin_ws/devel/setup.bash
+roscore -h
+rosversion clover
+rosversion aruco_pose
+rosversion mavros
+rosversion mavros_extras
+rosversion ws281x
+rosversion led_msgs
+rosversion dynamic_reconfigure
+rosversion tf2_web_republisher
+# rosversion compressed_image_transport
+# rosversion rosbridge_suite
+rosversion cv_camera
+rosversion web_video_server
+rosversion nodelet
+
+echo "Trying running the Gazebo simulator, check the output"
+timeout --preserve-status 30 roslaunch clover_simulation simulator.launch gui:=false --screen