Implement table styles

lib/notare/nodes/table.rb

@@ -3,11 +3,12 @@
 module Notare
   module Nodes
     class Table < Base
-      attr_reader :rows
+      attr_reader :rows, :style
 
-      def initialize
-        super
+      def initialize(style: nil)
+        super()
         @rows = []
+        @style = style
       end
 
       def add_row(row)