component email gateway: convert `autocrypt` header: Autocrypt header must be transmitted in both directions to allow opportunistic end-to-end encryption with this protocol. Moved email validation regex to `tools/common/regex.py`, as it can be used in other locations. rel 456

#!/bin/sh

eval $(dbus-launch --sh-syntax)

nohup /usr/bin/Xtigervnc -geometry 1024x768 -desktop "Libervia e2e test" -rfbport 5900 -SecurityTypes None :0 &
nohup openbox &
exec libervia-backend fg