OMEdit: Select multiple objects in DiagramView with [Shift] key (not with [Control] key)

[janK]

In OMEdit the selection of multiple objects in DiagramView is realized using the mouse click and the [control] key. In other applications like Dymola, Inkscape and Illustrator it is (just) click + [shift] key. In Solid Works and Word (Auto Forms) both [control] and [shift] key do work. In the textual context (a list element), multiple selection with [control] and [shift] do have a slightly different behavior.

In summary, I recommend changing the key in OMEdit from [control] to [shift] key, exactly how it is realized in Dymola, Inkscape and Illustrator.

[adeas31]

Done in d48d23a/OMEdit.