Add gallery.
- fixed eckert IV invert function
Merge remote-tracking branch 'fatzh/master'
Simplify and add tests for eckert4.invert.
Delete obsolete d3.cie plugin.
Add bullet.orient(top | bottom). Fixes #63.
d3.bullet: inherit transitions.
Link to vertical demo.
Update README.md
Add Airy’s minimum-error azimuthal projection.
Update README.md
Fix typo.
Add Chamberlin trimetric.
Add another Airy link.
Update README.md
Update README.md
Update README.md
Add inverse for d3.geo.interrupt.

This assumes non-overlapping bounding boxes for lobes.
Simplify slightly.
Add Gilbert’s Two-World Perspective.