Tool settings should be a dockable tab

[i-make-robots]

Is your feature request related to a problem? Please describe.
Select a group of poses. Rotate them. They will rotate around their individual origins, instead of a common origin.
The common origin cannot be adjusted, let alone set. This speaks to a bigger problem that any tool used in the 3D view might have sub-options and sub-controls, but there's nowhere to display them.

Describe the solution you'd like
Every tool should be able to provide a JPanel. It should populate the Tool dockable tab when the tool is selected.

Additional context
Should tool settings persist per-scene or globally?