Add README and arduino update tool

README.md

@@ -0,0 +1,6 @@
+Building and deployment
+=======================
+
+    $ cd arduino && pio run && cd ..
+    $ cd raspi/mgmt && ansible-playbook playbook.yml && ansible-playbook
+        arduino.yml

raspi/mgmt/arduino.yml

@@ -0,0 +1,8 @@
+- hosts: raspi
+  become: True
+  become_user: root
+  tasks:
+    - copy: src=../../arduino/.pioenvs/megaatmega2560/firmware.hex dest=/tmp
+    - systemd: state=stopped name=lightdm
+    - shell: avrdude -p m2560 -c wiring -P /dev/serial/by-id/* -b 115200 -D -F -U flash:w:/tmp/firmware.hex
+    - systemd: state=started name=lightdm

raspi/mgmt/playbook.yml

@@ -7,3 +7,4 @@
     - copy: src=autostart dest=/home/pi/.config/lxsession/LXDE-pi/autostart
     - copy: src=sejf.desktop dest=/etc/xdg/autostart
     - apt: name=python-flask state=present
+    - apt: name=avrdude state=present