Changes

| https://www.rhino3d.com/en/images/v5logo-m4.png || '''Rhinoceros 3D''' || 3-D modeling software || [https://www.rhino3d.com/download rhino3d.comdownload] || 3-D modeling software(free for 90 days, also full version is on lab machines)

| http://slic3r.org/images/logo.png || '''Slic3r''' || G-code generator for 3D printers || [http://slic3r.org/download download slic3r.org] || G-code generator for 3D printers (free and open source)