Add white to colours (#2853)

* add white to colorresolvable typedef

* add colour white

src/util/Constants.js

@@ -382,6 +382,7 @@ exports.ClientApplicationAssetTypes = {
 
 exports.Colors = {
   DEFAULT: 0x000000,
+  WHITE: 0xFFFFFF,
   AQUA: 0x1ABC9C,
   GREEN: 0x2ECC71,
   BLUE: 0x3498DB,

src/util/Util.js

@@ -245,6 +245,7 @@ class Util {
    * ```
    * or one of the following strings:
    * - `DEFAULT`
+   * - `WHITE`
    * - `AQUA`
    * - `GREEN`
    * - `BLUE`