Editor: reset camera after cell drag and drop

When replacing a viewed cell via drag and drop the camera position is
not updated to better view the new cell. This flags the camera position
as not being set so a better default is set.

apps/opencs/view/render/unpagedworldspacewidget.cpp

@@ -92,6 +92,7 @@ bool CSVRender::UnpagedWorldspaceWidget::handleDrop (const std::vector<CSMWorld:
     mCellId = universalIdData.begin()->getId();
 
     mCell.reset (new Cell (getDocument().getData(), mRootNode, mCellId));
+    mCamPositionSet = false;
 
     update();
     emit cellChanged(*universalIdData.begin());