`BinEdgeWidget` and improved `BinEdgeParam`

[SimonHeybrock]

Goal: Create a widget for defining bin edges from a given workflow parameter, based on and instance of BinEdgeParam.

The widget should be more compact than the current draft, i.e., everything in a single line.

Features:

• User can select between linspace and geomspace.
• Define start, stop, and num
• BinEdgeParam must be able to define defaults for the three required inputs.

Optional features (we may choose to ignore this initially, it might never be required):

• Select unit from a pre-defined set.
• Consider if we want/need bounds for the params. num<2 never makes sense so that can be automatic.