Improved auto-calibration

The auto-calibration can now work off highest-intensity and weighted
average rather than requiring a gaussian fit -- this is helpful in cases
where the beads aren't significant enough to detect conventionally (i.e.
using off-frequencies to stop them from showing up too brightly in
reconstructed data).

Improved some things in the iterative sphere fitter; it works alright
around a 90-degree sweep of beads, but as with the hypersphere fitter, it
works best with a full circle.

Signed-off-by: Luke Stuyvenberg <stuyvenberg@wisc.edu>
Bugfix on stage position importing

Only affected the sliders tab (which may be deprecated soon anyway); the
spinner number model had changed to Doubles instead of Integers, but the
cast was still to Integer.

Signed-off-by: Luke Stuyvenberg <stuyvenberg@wisc.edu>
Removed pixel size component from SPIMCalibrator

The SPIMCalibrator interface is now solely for determining the axis of
rotation. Before long it will likely be de-interfaced in favor of solely
the autocalibrator.

Signed-off-by: Luke Stuyvenberg <stuyvenberg@wisc.edu>
Further improvements to SPIMAutoCalibrator

Removed the min_sigma option for Z (it didn't work very well before, and
isn't possible/sensible with the new X/Y options). Also cleaned up bits
here and there, and added a circle representing the fit to the 3D view if
the axis has been determined.

Signed-off-by: Luke Stuyvenberg <stuyvenberg@wisc.edu>
Modified build scripts to accommodate Jenkins

Jenkins can't run openspim.sh, but still needs to get 3rdpartypublic, the
JDK, and Fiji... I moved those fetch bits into prepare-for-build.sh which
is invoked from build.sh; for most users, there won't be much difference,
since openspim.sh calls build.sh anyway.

Signed-off-by: Luke Stuyvenberg <stuyvenberg@wisc.edu>