Feature: Add searchgeom and validate it

This merge request adding searchgeom property to PARAMS and validate it.

Object type was added to parseValue (lib/util/params)

searchgeom is used for reverse geocoding.

It accepts geometry object

example:

{
    type: 'Circle',
    coordinates: [2.0, 48.5],
    radius: 100
}

The accepted geometry types are :

• Point
• LineString
• Polygon
• Circle

For the address index, only Polygon and Circle geometries are allowed.

@mapbox/geojsonhint lib was used to validate geometry except Circle