Backprojection parameters aren't descriptive

[nikolausWest]

Depth backprojection is very useful but it's currently hard to understand what it does because of naming and on-hover-descriptions in the selection view.

"Backproject scale" is derived from the meter parameter in the logging function log_depth_image. This blueprint (UI settable) parameter should be refactored to map 1:1 with the parameter in the log_depth_image. It should have a name that indicates as much and the on-hover description should explain how it works.

A scale indicates that this parameter multiplies another value. The on-hover description should indicate what value this scale multiplies.