Swapping tech should support range properties

[sprocter]

It should be possible to swap range properties.

Up for discussion, though, is how this would work. Here are some options:

1. Explicitly enumerate ranges
2. Range for min and max with enforcement that the min value is less than the max value, ie, min ≤ max
3. Range for min and max with enforcement that there's some specified (or variable 😐) gap between min and max, ie, min ≤ x ≤ max, where x is either user set or itself an ATSV-selected variable.