Improved the UX of the drag and drop interface.

Drop-targets being highlighted when drop units are hovered over.
Commands highlighting effect when reordering in the command list.
Allow for new commands to be inserted into anywhere in an existing list.
Constrained objects dragging within the dashboard container.
Added temporary data id tag to the dynamically generated commands in the procedures list.
Improve the control logic of the drag and drop.
Shifted drag and drop javascript into a dedicated js file.
Shifted drag and drop scss into a separate  scss file.