Consistent icon behavior

[itsrachelfish]

Currently there are two places where icons are used: when hovering over objects in the workspace and when hovering over slides in the slides menu.

The icons in the workspace act like buttons that change a specific mode. When you click the move icon, it enables move mode across all objects. If you click it again, it does the action. The icons in the slide menu don't do this, you simply click on them to perform the action. This behavior is definitely more intuitive and should be adopted for content as well.