Added test for isSubClass() with interface inheritance.
Added test for isSubClass() with interface inheritance.

jacksonic/vjlofvhjfgm,TanayParikh/foam2,foam-framework/foam2,TanayParikh/foam2,foam-framework/foam2,TanayParikh/foam2,foam-framework/foam2,jacksonic/vjlofvhjfgm,foam-framework/foam2,jacksonic/vjlofvhjfgm,TanayParikh/foam2,foam-framework/foam2