#14 Add diagnostic screen features

Some features to add to the "Diagnostic" screen:

• Reboot - touch /tmp/reboot_flag to trigger reboot
• Toggle eth0 - bring up or down the eth0 interface (ip link set eth0 up/down)
• Info - show select information about the system (SSH_TARGET variable, ps result of ssh processes running, etc.)

Note that some features might want to be restricted to production since they can give easy access to the system.