Updated RgbColor object API (markdown)

RgbColor-object-API.md

@@ -123,5 +123,9 @@ This will blend between four colors by the amount defined by 2d weighting values
 ### uint8_t operator[](size_t idx)
 The index operator allows accessing the R, G, and B properties using an index.  There are both read only and read write versions.
 ```
-   uint8_t green = color[1];
+   uint16_t green = color[1];
+```
+You can also use the color index constants.  
+```
+   uint16_t green = color[ColorIndexG];
 ```