Addes necessary model for SceneMap.
Adds FieldName and Selection attributes.
Adds new scene map actions and tests.
Changes some actions and tests.
DraggableGridLayout refactoring. New DropGridEvent, DropListEvent, etc.
GridLayout improvements.
Adds SceneMapWidget and SceneWidget.
Updates HomeView.
Renamed AddToMap to IncreaseMapSize action.
Adds some Q utility methods.
Changes actions to generate Cells in the SceneMap.
Merge pull request #692 from RotaruDan/modelSceneMap

SceneMapWidget, model...