Geometry: Adds padded on boxes

Signed-off-by: Romain Chanoir <chanoir.romain@courrier.uqam.ca>
Geometry: Introducing BoxedCollection

Signed-off-by: Romain Chanoir <chanoir.romain@courrier.uqam.ca>
QuadTree API Introduction

Signed-off-by: Romain Chanoir <chanoir.romain@courrier.uqam.ca>
Merge: QuadTree API introduction

QuadTree data structure API used to partition two-dimensional space. Includes a Static and a dynamic implementation, and a simple implementation with an array

Pull-Request: #472
Reviewed-by: Jean Privat <jean@pryen.org>
Reviewed-by: Alexis Laferrière <alexis.laf@xymus.net>
Reviewed-by: Alexandre Terrasa <alexandre@moz-code.org>