upgrade inkscape and pstoedit to Recommends

PyCAM currently shells out to inkscape and pstoedit to read SVG files -
without those helper programs, pycam cannot read SVGs.

The pycam debian package currently Suggests those dependencies, which
means that by default (unless the user explicitly selects them) they
won't be installed.

This commit upgrades the relationship from Suggests to Recommends,
so they'll be installed by default, making SVG work "out of the box".

debian/control

@@ -12,8 +12,8 @@ Architecture: all
 Depends: python-gtk2, python-opengl (>>3.0.0~b6-3), python-gtkglext1,
  python-rsvg, ${misc:Depends}, ${python:Depends}
 Recommends: python-pyode (>>1.2.0-3), python-psyco, python-setproctitle,
- python-guppy
-Suggests: inkscape, pstoedit, qcad-data | librecad-data
+ python-guppy, inkscape, pstoedit
+Suggests: qcad-data | librecad-data
 Description: CAM program & Python library for generating toolpaths
  PyCAM is a toolpath generator for 3 axis machines. The generated
  GCode can be used with EMC2 and other machine controllers.