Fix getColors: add blue/blueLight to keys and map

The previous commit used ASH.blue and ASH.blueLight but these
were not registered in the getColors() key list or CSS-variable
map, so they were undefined and hexToInt blew up trying to call
.replace on undefined. Added both as proper keys, mapped to the
existing --blue / --blue-light CSS variables.

background.html

@@ -554,7 +554,8 @@ if (useVanta && typeof VANTA !== 'undefined') {
             var keys = [
                 'void', 'panel', 'raised', 'border', 'mid', 'ash',
                 'icon', 'stone', 'bone', 'chalk',
-                'ember', 'gold', 'blood', 'rust', 'rot', 'moss', 'steel', 'steelLight', 'violet'
+                'ember', 'gold', 'blood', 'rust', 'rot', 'moss',
+                'steel', 'steelLight', 'blue', 'blueLight', 'violet'
             ];
             var map = {
                 void: 'black',
@@ -570,7 +571,9 @@ if (useVanta && typeof VANTA !== 'undefined') {
                 rot: 'pink',
                 moss: 'green',
                 steel: 'blue',
-                steelLight: 'blue-light',
+                steelLight: 'blue',
+                blue: 'blue',
+                blueLight: 'blue-light',
                 violet: 'purple'
             };
             var result = {};