This commit addresses warnings that were raised by QtCreator's linter:
- IDs declared more than once
- variables declared more than once in the same scope
- type coercions
- variables declared as "var" when their type is known
- unclosed "case" in switch-case
- Special entity acting as an object container: we can add the entities we want to control with a gizmo inside it.
- Drawing the gizmo always on top of the object to make sure to see it every time.
Keyboard Actions are never deactivated when focus is lost, leading to picking being enabled on a single click when Control was pressed in the 3D viewer and focus was lost to another Item.
* keep track of focus loss inside the DefaultCameraController
* use it to disable picking while Keyboard has not been pressed back in the 3D viewer
* do the same for 'moving' state with Alt modifier
