Function Slide for vctrans vapoursynth Plugin

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Slide

The transition from Clip A to Clip B occurs as sliding in or out action in a desired direction.

## trans.Slide(clip, clipb clip[, float overlap = 1.0 ][, int dir = 1][, int slidein = 1] )

Parameter description:
clip : A clip. Constant format.
clipb : B clip. Must have identical format of A clip
overlap : transition time length in seconds. Floating point. Must correspond to at least 8 frames.
dir : 1 to 8. 1:N in a clockwise direction with 8 for NW
slidein : 1: B slides in to view over stationary A. 0: A slides out over stationary B.
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