import first plotting class used in Autodesk Inventor 11
add id keywords
added usage example
used in Autodesk Inventor 2009:
 - Property IFeatures renamed to its real name IProperties
 - User output strings now in Structure
 - UpdateStile renamed to UpdateStyles
 - filled in "doxygen" xml comments
id keywords
subs for new inventor translator addins for dwf and pdf
renamed class to InventorPlotClass
some changes in xml comments
class changed to InventorPlotClass