Topic: v1.5.1 conversion

i have begun the conversion.  here is the todo/progress list:

(done) dimension2d.h
  (done) - new -= operator overload
(done) IMeshManipulator.h
  (done) - renamed scaleTCoords param from layer to level
(done) IrrlichtDevice.h
  (done) - new method isDriverSupported
(done) irrMath.h
  (N/A) - new function iszero
(done) irrXML.h
  (N/A) - new params createIrrXMLReader, createIrrXMLReaderUTF16, createIrrXMLReaderUTF32
(done) ISceneNode.h
  (done) - new method getSceneManager
  (done) - drawVertexPrimitiveList - added defaults params vType and on
  (done) - new method draw2DRectangleOutline

(done) rect.h
  (done) - new typedefs recti/rectf
  (N/A) - converted getHardwareMappingHint into getHardwareMappingHint_Index and getHardwareMappingHint_Vertex
  (N/A) - new param for setHardwareMappingHint

Re: v1.5.1 conversion

sorry it took so long!