Fix Bug 695: WGLExt.wglChoosePixelFormatARB causes buffer underflow due to a higher reported number of configs than buffer size

"I encountered a case on an NVidia Quadro 3500 fx where the call to
WGLExt.wglChoosePixelFormatARB in WindowsWGLGraphicsConfiguration (currently
line 355) returns 264 in numFormatsTmp despite 256 being passed in for the
maximum number of formats. This results in a buffer underflow on line 368 since
pformatsTmp only has 256 values and it's trying to copy 264 values."

Fixed in WindowsWGLGraphicsConfiguration and WindowsPbufferWGLDrawable.