Tippecanoe

* Features that cross the antimeridian are split into two parts instead
of being partially lost off the edge

* More polygon correctness
* Query the system for the number of available CPUs instead of guessing
* Merge input files into one layer if a layer name is specified
* Document and install tippecanoe-enumerate and tippecanoe-decode

* Tile generation is multithreaded to take advantage of multiple CPUs
* More compact data representation reduces memory usage and improves speed
* Polygon clipping uses [Clipper](http://www.angusj.com/delphi/clipper/documentation/Docs/_Body.htm)
and makes sure interior and exterior rings are distinguished by winding order
* Individual GeoJSON features can specify their own minzoom and maxzoom
* New `tile-join` utility can add new properties from a CSV file to an existing tileset
* Feature coalescing, line-reversing, and reordering by attribute are now options, not defaults
* Output of `decode` utility is now in GeoJSON format
* Tile generation with a minzoom spends less time on unused lower zoom levels
* Bare geometries without a Feature wrapper are accepted
* Default tile resolution is 4096 units at all zooms since renderers assume it

* Switched to top-down rendering, yielding performance improvements
* Add a dot-density gamma feature to thin out especially dense clusters
* Add support for multiple layers, making it possible to include more
than one GeoJSON featurecollection in a map. [29](https://github.com/mapbox/tippecanoe/pull/29)
* Added flags that let you optionally avoid simplifying lines, restricting
maximum tile sizes, and coalescing features [30](https://github.com/mapbox/tippecanoe/pull/30)
* Added check that minimum zoom level is less than maximum zoom level
* Added `-v` flag to check tippecanoe's version