SimplePartWhole - camelCase

Hi,

This is a minor nitpick, and the note at the bottom of the working draft 
suggests that this has been brought up already, but it would be nice if 
the properties in SimplePartWhole were in OWL-convention camel case 
instead of having underscores, like partOfDirectly instead of 
partOf_directly.  Otherwise it looks good!

Thanks!
Dave Kolas