added config_tag plugin for integration of configuration into templates

plugins/config_tag.rb

@@ -0,0 +1,29 @@
+require 'json'
+
+class ConfigTag < Liquid::Tag
+  def initialize(tag_name, options, tokens)
+    super
+    @options = options.split(' ').map {|i| i.strip }
+    @key = @options.first
+    @tag = (@options[1] || 'div')
+  end
+
+  def render(context)
+    config = context.registers[:site].config
+    options = @options.first.split('.').map { |k| config = config[k] }.last #reference objects with dot notation
+    keyclass = @key.sub(/_/, '-').sub(/\./, '-')
+    tag  = "<#{@tag} class='#{keyclass}'"
+    options.each do |k,v|
+      unless v.nil?
+        v = v.join ',' if v.respond_to? 'join'
+        v = v.to_json if v.respond_to? 'keys'
+        tag += " data-#{k.sub'_','-'}='#{v}'"
+      end
+    end
+    tag += "></#{@tag}>"
+    p tag
+    tag
+  end
+end
+
+Liquid::Template.register_tag('config_tag', ConfigTag)