Now shape scaling is handled through the transform dialog instead of
simulating a drag and drop event in core.

For Impress the unit used for length is '100th mm' instead of twips,
so we need to transform positions and size from twips to '100th mm'.
Anyway since we don't know in SetGeoAttrToMarked if the new data is
due to a mouse event or by entering a new value in the transormation
dialog or in the side pane, for Impress we need to convert the new
values sent by the dialogs from '100th mm' to twips which are
converted back in SetGeoAttrToMarked.

For performing a uniform scaling when the shape/image is rotated we
need to inform the client about the rotation angle for the selected
graphic object that has been achieved but appending an angle argument
to the graphic selection callback.

Now it is also possible to reverse shapes/images through negative
scaling.

Change-Id: I8a32f3e4b28f36e884a59c59b7e1351e85ef4489
Reviewed-on: https://gerrit.libreoffice.org/64696
Tested-by: Jenkins
Reviewed-by: Jan Holesovsky <kendy@collabora.com>