Updated Brushes (markdown)

Brushes.md

@@ -46,7 +46,7 @@ local randomColor = Brushes.GetRandomColor();
 ```
 ---
 ### GetRelativeColor
-Returns the color at the given position in a gradient.
+Returns the color at the given position in a gradient, relative to the gradient's start.
 #### Syntax:
 ```lua
 color GetRelativeColor(table gradientColors, double position);