* 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/trunk@39384 b2dd03c8-39d4-4d8f-98ff-823fe69b080e