Fix a line clipping edge case

Fix the edge case when a line string enters the clip region from outside and has a node exactly on the clip region border.
Before, the node on the border was skipped, which caused wrong line metrics estimation.

Use google benchmarks and fix minor performance issues (mapbox#91)

* Convert benchmarks to google benchmark

* Reserve container sizes and emplace elements

* Update xcode version for macOS bot

* Don't copy properties during index generation

* Move clipped rings

Update to geometry v1.0.0 & geojson v0.4.3

fix a polygon clipping edge case

Port of mapbox/geojson-vt@2ba995a

use ::hypot from libc instead of the STL version

Add a line metrics test for a single tile

This patch also fixes buffer rounding in `geoJSONToTile()`.

Based on patch from @lbud (Lauren Budorick).

Fix compilation errors on OSX (mapbox#77)

This fixes compilation errors on OSX when -Werror,
-Wshorten-64-to-32 flags are passed to the compiler.

Update geometry to v0.9.3

formatting fixes with make format

inline geoJSONToTile()