Specifying -keyboard clone (or keyboard=clone in options) will clone
XKB keyboard from the remote x server. This way many keyboard problems
will hopefully never return...

Should be the default but is not (yet) for compatibility reasons.

Fixes ArcticaProject/nx-libs#373

(except the "do autoconf if no keyboard is provided" feature.)

References:
  ArcticaProject/nx-libs#240
  ArcticaProject/nx-libs#368