To be consistent with the Graph Editor behavior, double clicking on a node sets it as the active node of its type. This, for example, enables to switch from one SfM to another from the media list.
* Inspector
* changed "SETTINGS" to "DISPLAY"
* new "CAMERA" section: activate camera synchronization + control image overlay
* ImageOverlay: new component to display (undistorted) image on top of the 3D view
* ViewpointCamera: new component that sets up a Camera based on a Viewpoint internal parameter
* Viewer3D: additional ViewpointCamera to perform synchronization with image selection
* Viewer3DSettings: new properties related to camera synchronization mode
Contextual menu to expose additional actions:
* open media containing folder
* copy media path
* advanced manual control over media (un)loading
+ fix MediaLibrary to avoid binding loop on 'visible' when directly modifying 'request' property
* Define 2 groups: "Settings" and "Scene"
* Settings
* add camera scale slider control
* move rendering modes back to an independent overlay outside the inspector
* Scene
* add button to control visibility of media info
* ease bidirectional navigation between 3D media list and graph
* use same mechanism to indicate selected/hovered elements
* remove 'frame' button (space gain + action available on double click)
* remove the notion of manual media (un)loading from high-level UI
* visibility button now drives media loading:
* if media is not available (not yet computed), it will be loaded once available if visibility is on
* once loaded, media can't be explicitly unloaded
* use an icon to indicate that the media is not available instead of colors
