Match circle color with github linguist (#630)

* add circle color to macro

* update CONTRIBUTING.md

CONTRIBUTING.md

@@ -15,9 +15,9 @@ Adding support for a new Language consists in adding a new entry to the `define_
 
 **Example**:
 
-`{ TypeScript, Programming, "typescript.ascii", define_colors!([Cyan, White] : [Rgb(0, 122, 204), Rgb(255, 255, 255)]) }`
+`{ TypeScript, Programming, "typescript.ascii", define_colors!([Cyan, White] : [Rgb(0, 122, 204), Rgb(255, 255, 255)]), Rgb(43, 116, 137) }`
 
-The first item `TypeScript` corresponds to the name of the language as defined in [tokei](https://github.com/XAMPPRocky/tokei). The second item refers to the language type as specified by [linguist](https://github.com/github/linguist/blob/master/lib/linguist/languages.yml), only four values are possible: Programming, Markup, Prose and Data. The third item `typescript.ascii` is the name of the file containing the ascii logo: this file has to be placed in the _./resources_ folder (more info below). Then we have the colors used to customize the look of the ascii logo when displayed to the screen.
+The first item `TypeScript` corresponds to the name of the language as defined in [tokei](https://github.com/XAMPPRocky/tokei). The second item refers to the language type as specified by [linguist](https://github.com/github/linguist/blob/master/lib/linguist/languages.yml), only four values are possible: Programming, Markup, Prose and Data. The third item `typescript.ascii` is the name of the file containing the ascii logo: this file has to be placed in the _./resources_ folder (more info below). Then we have the colors used to customize the look of the ascii logo when displayed to the screen. Finally, the circle color used in the language distribution as specified by [linguist](https://github.com/github/linguist/blob/master/lib/linguist/languages.yml).
 
 #### Ascii logo