Texture filtering user control for IplImageVisualizer

[RoboDoig]

Allows a user to switch texture filtering modes on the editor window for IplImage

Button added to bottom status strip, toggles between nearest and linear filter modes for the display texture

[RoboDoig]

Toggle doesn't work if multiple IplImage windows are open in editor. E.g. 1 ConvertToImage and 1 CameraCapture window. Closing the 2nd window causes it to work again.

[CLAassistant]

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