X.L.NoBorders: Fix docs of data Ambiguity
X.L.NoBorders: Fix docs of data Ambiguity

In c6cdb77e3b3d6a3842b914a0cf64357f03fcf0c1, several new constructors
were added but not "In order of increasing ambiguity (less borders more
frequently)" as the docs for data Ambiguity say. Correct the order and
clarify that Never only considers ambiguity of tiled windows (as in the
doc for smartBorders).

Fixes: c6cdb77e3b3d ("'XMonad.Layout.NoBorders': various improvements:")
Related: https://github.com/xmonad/xmonad-contrib/issues/280

xmonad/xmonad-contrib,xmonad/xmonad-contrib