Sets or returns the object's mass. Read/write Double.
When a Bot object is created, its mass is initialized to 1.
In this example, three Bot objects are created and each assigned a mass value.
Set Sun = Bots.Create (1)
Set Planet = Bots.Create (1)
Set Moon = Bots.Create (1)
Sun.Mass=1000
Earth.Mass = 1
Moon.Mass = .01