JSON: made support_minimal_diameter child of support_tower_diameter (CURA-870)
JSON: made support_minimal_diameter child of support_tower_diameter (CURA-870)

hmflash/Cura,hmflash/Cura,ynotstartups/Wanhao,fieldOfView/Cura,Curahelper/Cura,ynotstartups/Wanhao,totalretribution/Cura,senttech/Cura,fieldOfView/Cura,senttech/Cura,Curahelper/Cura,totalretribution/Cura