FR: Reboot button

Having a reboot button on the web UI could be useful in cases where the ESP connects to the wrong access point, or just loses connection to the Panda Touch while still remaining connected to the network.

At the moment, the only two ways of restating it are to either pull the plug (which obviously requires me to be near it), or to upload a firmware upgrade which will restart it once complete (which also wears off the flash)

Start by locating the web UI controls and the firmware path involved when an upgrade restarts the device. Trace how a UI action reaches the ESP, then verify that a reboot can be requested without reflashing and that the action works when the device remains connected to the network.

Written by the indexing model from the issue text.