--------- Slave ------------------------------
http://blog.gbaman.info/?p=791
http://blog.gbaman.info/?p=699
https://learn.adafruit.com/turning-your-raspberry-pi-zero-into-a-usb-gadget/ethernet-gadget
https://learn.adafruit.com/turning-your-raspberry-pi-zero-into-a-usb-gadget/ethernet-tweaks
https://learn.adafruit.com/adafruits-raspberry-pi-lesson-4-gpio-setup/configuring-i2c
http://wiringpi.com/download-and-install/
http://www.vincenzov.net/tutorial/RaspberryPi/wiringpi.htm
sudo apt-get install python-pip
http://www.knight-of-pi.org/digital-sensors-and-the-raspberry-pi-with-the-smoke-detector-mq-x-as-example/
http://makezine.com/projects/tutorial-raspberry-pi-gpio-pins-and-python/

-------Bluetooth Master-----------------------
http://stackoverflow.com/questions/21597536/pybluez-installation-in-linux
https://learn.adafruit.com/install-bluez-on-the-raspberry-pi/installation
https://www.raspberrypi.org/magpi/create-a-raspberry-pi-3-bluetooth-tag/
https://www.raspberrypi.org/forums/viewtopic.php?f=28&t=138145
https://www.raspberrypi.org/forums/viewtopic.php?f=63&t=133263 #risposta di: by Douglas6 » Tue Jan 19, 2016 11:00 pm 

sudo apt-get install libboost-thread-dev
pip install gattlib
sudo apt-get install mercurial
hg clone https://bitbucket.org/OscarAcena/pygattlib
cd pygattlib
sudo python setup.py install


Attivare il bluetooth
Rendere il rasp visibile
Fare l'associazione
Poi il programma va!
---------Mongo DB command------------------------
mongod --auth --dbpath D:\server --sslMode requireSSL --sslPEMKeyFile D:\server\ssl\mongodb.pem

sudo mongod --auth --fork --dbpath ~/si --logpath /var/log/mongodb/mongod.log --sslMode requireSSL --sslPEMKeyFile /etc/ssl/mongodb.pem


https://docs.mongodb.com/manual/tutorial/configure-ssl/
https://docs.mongodb.com/manual/tutorial/enable-authentication/

use test_database
db.createUser(
  {
    user: "",
    pwd: "",
    roles: [ { role: "readWrite", db: "test" },
             { role: "read", db: "reporting" } ]
  }
)

http://stackoverflow.com/questions/9038547/mongodb-update-every-document-on-one-field
https://docs.mongodb.com/manual/tutorial/update-documents/
https://www.tutorialspoint.com/mongodb/mongodb_update_document.htm
https://docs.mongodb.com/manual/reference/operator/update-array/
https://docs.mongodb.com/manual/reference/operator/update/push/#up._S_push
https://docs.mongodb.com/manual/core/shell-types/