DPI is now property of the job part and its double not int

src/com/t_oster/liblasercut/JobPart.java

src/com/t_oster/liblasercut/LaserCutter.java

src/com/t_oster/liblasercut/LaserJob.java

src/com/t_oster/liblasercut/Raster3dPart.java

src/com/t_oster/liblasercut/RasterPart.java

src/com/t_oster/liblasercut/VectorPart.java

src/com/t_oster/liblasercut/drivers/EpilogCutter.java

src/com/t_oster/liblasercut/drivers/EpilogHelix.java

src/com/t_oster/liblasercut/drivers/EpilogZing.java

src/com/t_oster/liblasercut/drivers/LaosCutter.java

src/com/t_oster/liblasercut/drivers/Lasersaur.java

src/com/t_oster/liblasercut/examples/PhotoPrint.java

test/com/t_oster/liblasercut/drivers/LaosCutterTest.java