Wrap longitudes and improve antimeridian stitching.

I disabled the “quantization precisely preserves minimum and maximum
values” test as longitude wrapping changes this slightly.
Checkpoint broken stitching.
Fixes.
Mostly fix.
It works!
Delete whitespace.
Normalise spherical coordinates.

As well as wrapping longitudes, we also choose a consistent longitude
for polar points, to aid stitching of antimeridian cuts.
Only stitch in polar coordinates.
Fix two tests.
Fix last test.
Fix require.
Tweak quantization in test.
Re-enable test.
Update examples.
Stitch more than two fragments together.

This fixes an issue when stitching the 50m ocean example.
Consolidate shared code.
Rename stitch-poles.js to stitch.js.

The option name still remains as "stitch-poles", even though it stitches
anything that crosses the antimeridian.
Regenerate examples.
Merge branch 'stitch-simple'