Selection Box

We want to be able to drag a box around entities for selection. Selected entities will show up in a panel and be highlighted.

Requirements

Mouse click, hold, and release events for dragging a box
A box appears when the mouse is held and dragged
Entities with in the box are highlighted
When the mouse is release, the highlighted entities are displayed in a panel.
There is a different highlighted color for entities that are selected and ones that are in a box to be highlighted upon mouse up event