* Put back fl_min=0 as it is for all other devices (the idea
fl_min should be 1 and toggling managed some other way is
not implemented in current code).
* Fix a few frontlightwidget issues
* Use PluginShare to exchange data between plugins
* Remove legacy code in reader.lua and kobo/device.lua, and move KOBO_LIGHT_ON_START to kobo/powerd.lua
* A better sync config logic
* Consider kobo without hardware frontlight toggle
* update frontlight widget once toggle is tapped.