Adapt WHEAMM competition functions to WALTer outputs

[MeijeGawinowski]

Adapt competition functions with dictionnary lists plant_map={['plant_id'] : x,y}, neighbours_list = {['plant_id'] : [neighbours_id]} and info_plants = {['plant_id'] : surface, height} and later influence_plants = {['plant_id'] : ri} with ri the radius of the influence surface. Make connection between these functions in competition_wheamm.py and WALTer outputs.