In ~/sketchbook/hardware I have a folder for the LeoStick.
It appeared in the Boards list with version 1.0.5, but is not seen in version 1.5.6-r2.
How do I get it back?
I also added a folder for ATtiny85. It too is ignored.
I got the LeoStick back by moving the contents of hardware/Leostick to hardware/avr/Leostick.
The ATtiny85 was recognised once I changed Boards.txt to boards.txt...