fixes #0001684: Sweep ignores the list of subshapes
Merge branch 'master' of ssh://git.code.sf.net/p/free-cad/code
Draft - Allow to export Drawing pages to DXF - fixes #1686

* Uses DXF algos of the Drawing module instead of the Draft dxf library
* Uses a DXF template with the same name as the SVG template, if existing
* Only Draft, Arch, Part and Annotation views are currently supported
* Drawing module's projectToDXF() now returns only a fragment instead of a full DXF file