Improve Path tool layer and anchor point selection behavior

[Keavon]

• [ ] Deselects the shape layer (from the layer panel) when clicking into empty space
• [ ] Selects all the shape's layer (in the layer panel) and selects all the anchor points when clicking in the filled area of the shape
• [ ] Selects the targeted shape when dragging (regardless of whether or not it was previously a selected layer or whether it had any or some or all anchor points selected) and then drags the whole shape similar to the Select tool
• [ ] Selecting an individual anchor point deselects all but the clicked one (and shift select adds/removes to/from the selection)