implement color picking from predefined set for category badges + option to change foreground color

app/serializers/category_excerpt_serializer.rb

@@ -3,7 +3,7 @@ require_dependency 'excerpt_type'
 class CategoryExcerptSerializer < ActiveModel::Serializer
   include ExcerptType
 
-  attributes :excerpt, :name, :color, :slug, :topic_url, :topics_year,
+  attributes :excerpt, :name, :color, :text_color, :slug, :topic_url, :topics_year,
              :topics_month, :topics_week, :category_url, :can_edit, :can_delete
 
 

app/serializers/category_serializer.rb

@@ -3,6 +3,7 @@ class CategorySerializer < ApplicationSerializer
   attributes :id,
              :name,
              :color,
+             :text_color,
              :slug,
              :topic_count,
              :description,