Fix: Now checking and clamping to [0.0, 1.0)

Now checking and clamping to 0-inclusive-to-1-exclusive instead of just 0-1-inclusive.  Including 1.0 as a possible value was occasionally causing genDestImagePixelBytes()’s `nearestTexelX`/`Y` values to equal the `destWidth`/`Height`, which at times caused bad memory access outside of `srcBytes`’ data, and other times caused missing (NAN probably) graphics especially in OutsideOfQuadUVClamp mode.

• `within_f` replaced (in function and usage) with `inRangeInclusiveExclusive_f()`.
• `within01_f` replaced (in function and usage) with `inRange0ToJustUnder1_f()`.
• `clamp01_f` replaced (in function and usage) with `clamp0ToJustUnder1_f()`.
	• New constant `kJustUnder1_0f` stores the next possible float value under 1.0f (roughly `0.99999994`), calculated using the nexttowardf() library function.