see: http://gluon.readthedocs.org/en/latest/releases/v2014.3.html



Signed-off-by: Alexander Dahl <alex@netz39.de>

The file targets/$GLUON_TARGET/config becomes optional, as many targets
only used it to set the board and subtarget.

Also fix targets without subtarget.

Fixes #373

Fixes #347

This adds mesh_on_lan functionality.

A new optional site.conf option, mesh_on_lan, has been added. If set to
'true', all LAN ports will be used for meshing instead of being part of
the client bridge.