ttools: add option to anchor plane X/Y axes at data value of zero

This is specially useful for histogram, since it means you can fix
the X axis to sit at the bottom of the plot.
Realised while doing this that the configuration parameters for
navigators really belong with the SurfaceFactory not with the Navigator
itself.  Rectified this for PlaneSurfaceFactory (and histogram),
but not for Time, Sky, Cube etc.
topcat: adjust ControlWindow layout

Fix the window size so that it's determined by its contents and the
size is not hard-wired - although it looked OK on my machine, on Mac
the window was a bit small and needed scrolling.

Also add a few pixels spacing where some of the components were squashed
together and looked a bit ugly.
topcat: fix focus again

The change I made at 25775f6 grabbed focus for input fields (rather than
the toolbar) in a QueryWindow.  I did it by calling pack() explicitly,
but it turns out that causes weird problems elsewhere (e.g. part of
the ActivationQueryWindow being blanked out, I have no idea why).
I had a bad feeling about it anyway.

Now I've replaced that code by something more respectable which uses an
AncestorListener to wait until it's OK to call requestFocusInWindow.
Seems to be OK.
topcat: rename method name to avoid java1.7 name clash

Pointed out by Laurent Bourges.
ttools: add antialiasing option for plot grid text/line drawing

A new config option, GRID_ANTIALIAS, is added for all plot types.
This is partly so you can choose whether you want grids and labels
antialiased.  However, it's also to work around a MacOS java bug
that paints non-horizontal text all wrong.  If the text is antialiased,
it gets it right.  So on MacOS default to antialiased.  This isn't
particularly satisfactory (antialiased is slower, and I don't like
plaform-dependent behaviour) but it's better than having backwards text.