Bugfix: Work Item CP20604 - Adding Sheet to Workbook Bug
Extend headers to handle IE 9 problems and IE/SSL caching problems
Bugfix: Work item CP20703 - Calculation engine incorrectly evaluates empty cells as #VALUE
Disabled libxml external entity loading by default.

If you want to allow loading external entity references in XML, call PHPExcel_Settings::setLibXmlLoaderOptions(0).
Merge pull request #322 from maartenba/develop

Disabled libxml external entity loading by default.
Updated documentation for XXE injection in readers
Warning in security docs
AS we're using simpleXML for xml reading still, we need to use libxml_disable_entity_loader(true); for XXE security patch
When libxmlloader options are teh default values, disable the entity loader as well. CVE-2014-2054 by MITRE
Merge pull request #323 from maartenba/develop

When libxmlloader options are the default values, disable the entity loader as well. CVE-2014-2054 by MITRE
Update security section in Reader documentation
Merge branch 'develop' of https://github.com/PHPOffice/PHPExcel into develop
Hopefully final tweak for XXE to prevent displaying errors if SimpleXML isn't available