@mapbox/mapbox-gl-geocoder 4.0.0 on Node.js NPM

This is the full GA release for the v4.0.0 changes described in #197.

From the changelog:

Support for the Mapbox GL JS 0.47.0 API. This is compatible with 0.47.0 and later, and may not be compatible with earlier versions #219.
Obtain language from user's browser settings #195
Localize placeholder based on language set in constructor options #150
trackProximity turned on by default #195

Mapbox events upgraded to v0.2.0 for better handling #212
Pass flyTo options to the map on result selection on both map#flyTo and map#fitBounds operations #214 and #227
Bump suggestions dependency to v1.4.x
Adds the marker constructor option that allows adding the selected result to the map as a marker. Adding the marker to the map is now the default behavior. #219.
Add get and set methods for constructor options #226
Add collapsed option to collapse the geocoder controller into a button until hovered or focused #222
Expose clear as public method #115