* add WorkspaceView that contains Meshroom main modules (ImageGallery, 2D/3D viewer)
* add Panel component to standardize UI modules layout
* ImageGallery:
* add images basename on image delegates
* add explanatory placeholder when no image has been added to the reconstruction yet
* keep an internal reference to the "main" CameraInit node an update it according to graph modification
* expose viewpoints model as a property
* TODO: handle multiple CameraInit nodes
* cache last loaded image and display it while the main Image is loading to avoid empty screen
* fix the BusyIndicator by dynamically creating a binding on the running property (Qt bug ?)
* remove DiffuseMapMaterial automatically created by the SceneLoader
* use MaterialSwitchers to create and dynamically switch materials on loaded Entities
* add a "Textures" checkbox to perform the toggle
* add DefaultCameraController:
* mouse-only navigation
* keyboard modifiers fallbacks for view re-centering (Ctrl+LeftClick) and fast zooming (Alt+RightClick)
* improved double click handling for 3D Object Picking
* moved logic/Timer to the CameraController
* always use TrianglePicking but only activate the ObjectPicker when necessary
From Qt docs: "The Qt Labs Platform module uses Qt Widgets as a fallback on platforms that do not have a native implementation available. Therefore, applications that use types from the Qt Labs Platform module should link to QtWidgets and use QApplication instead of QGuiApplication."
* new footer that displays the number of images / allow to change thumbnail size
* smaller sourceSize for thumbnails (faster to load)
* avoid Nan scales in Viewer2D when no image is loaded
* add Rotation/Scale controls
* add controls to disable default items (grid/locator)
* add drop support to load external 3D models
* add "View All" action in contextual menu to fit to scene
* automatically propose to load the reconstructed mesh when available
* add button to submit the graph to the default submitter
* add warning message when the graph is being computed in another meshroom instance
* make Start button green
* core: NodeChunks are now stored in a ListModel inside Node
* ui: introduce SortedModelByReference
* ui: UIGraph exposes a proxy model of its graph's nodes sorted as visited by DFS (instead of another model of chunks)
* ui: added NodeChunks Component
* call removeEdge instead of removing the edge in the model. This allows to trigger signals at the Attribute level (like isLinkChanged)
* trigger graph update after node removal
