Add Multiple Selection and Box Selection #92
Description
Is your feature request related to a problem? Please describe.
The user has to move each element individually in order to reorganize the diagram.
Describe the solution you'd like
The application should be able to have the multi-element selection to translate many items with a single move. This kind of selection should be performed while selecting objects consecutively pressing SHIFT, or when the cursor in drag mode draws a selection box from and empty space of the screen.