merge revision(s) 39384:

	* lib/rexml/document.rb (REXML::Document.entity_expansion_text_limit):
	  new attribute to read/write entity expansion text limit.  the default
	  limit is 10Kb.

	* lib/rexml/text.rb (REXML::Text.unnormalize): check above attribute.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_3@39385 b2dd03c8-39d4-4d8f-98ff-823fe69b080e