add missing roof furniture

data/json/furniture_and_terrain/furniture-roof.json

• f_cellphone_booster
• f_small_satelitte_dish
• f_chimney
• f_TV_antenna
• f_vent_pipe
• f_roof_turbine_vent

data/json/furniture_and_terrain/terrain-zlevel-transitions.json

• t_ladder_up
• t_ladder_down

other stuff

• cooling unit
• f_solar_unit

Maybe the rain gutters can also see some more details from the current blueish squares.

Currently it looks like this: