Add STONITH with sms reboot sent to electrical outlet

[branciard]

Objective : prevent double signing of several active validators up and running

To do so, implement a https://en.wikipedia.org/wiki/STONITH algorithm ("Shoot The Other Node In The Head") with sms between federation nodes to reboot current validator DappNode thanks to electrical outlet reboot.

Before taking the leadership, a passive node send a restart sms on the electrical outlet of the current validator that is detected as down. The passive node will take the leadership and start as validator only if confirmation received of the sms command ( reboot confirmed of the electrical outlet). When a DAppNode reboot, archipel package will always start as passive and not validator. Thanks to this, It will reduce considerably the risk of double signing in archipel High availability solution.

• Modify CLI and Zip to add this STONITH sms optional feature
• Modify orchestrator
• Electrical outlet hardware used : http://www.iqtronic.com/products/gsm-switch-iqsocket-mobile/
• SMS API to use https://www.twilio.com/
• Sim card ( free mobile 2 euros/month)

qtronic outlet Sms commands and responses confirmation looks like :

qtronic outlet Sms DAppNode start by sms

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