Add monkey patch to fix cucumber docstrings:

Cucumber chomp the last \n from multiline strings (docstrings), this
monkey patch modify Cucumber::Ast::DocString constructor to add the
missing ending new line character and
Cucumber::Formatter::Pretty#doc_string to remove it from the output.

features/support/env.rb

@@ -14,3 +14,28 @@ module Cucumber
 end
 
 require 'aruba/cucumber'
+
+
+require 'cucumber/formatter/pretty'
+
+module Cucumber
+  module Ast
+    class DocString
+      alias :old_initialize :initialize
+
+      def initialize(string, content_type)
+        old_initialize(string + "\n", content_type)
+      end
+    end
+  end
+
+  module Formatter
+    class Pretty
+      alias :old_doc_string :doc_string
+
+      def doc_string(string)
+        old_doc_string(string.chomp)
+      end
+    end
+  end
+end