Double quote support for SUMIF() condition

Bugfix: Work item CP20760 - Formula references to cell on another sheet in ODS files

When libxmlloader options are the default values, disable the entity loader as well. CVE-2014-2054 by MITRE

When libxmlloader options are teh default values, disable the entity loader as well. CVE-2014-2054 by MITRE

AS we're using simpleXML for xml reading still, we need to use libxml_disable_entity_loader(true); for XXE security patch

Disabled libxml external entity loading by default.

If you want to allow loading external entity references in XML, call PHPExcel_Settings::setLibXmlLoaderOptions(0).

SUMIF() condition can have double quote, such as '=SUMIF(A2:A4,">""",B2:B4)'.
This formula purpose is to compare the character double quote (").

In our previous patch (commit f1a1f525) we wrongly assumed that
PHPExcel_Calculation_MathTrig::SUMIF() expected the condition to escaped ('>""'),
but this is actually not the case in real use of PHPExcel, so the unit tests were
modified accordingly to use non-escaped condition ('>"').

Bugfix: (EliuFlorez) Work item GH-279 - Fatal error: Call to a member function cellExists() line: 3327 in calculation.php if referenced worksheet doesn't exist

Update Calculation.php

Bugfix: Work Item GH-257 - Passing an array of cells to _generateRow() in the HTML/PDF Writer causes caching problems with last cell in the range

Bugfix: Work Item GH-275 - Insert New Row/Column Before is not correctly updating formula references

Bugfix: Work Item GH-275 - Insert New Row/Column Before is not correctly updating formula references

PHPExcel Fatal error: Call to a member function cellExists() line: 3327

Mods to handle encrypted files on both 32-bit and 64-bit versions of PHP - currently only tested on 32-bit Windows

Convert properties to string in OOCalc reader

Feature: (trvrnrth) Work Item GH-261 - Add support for reading protected (RC4 encrypted) .xls files (tweaked for PHP 5.2 compatibility)

Binary comparaison of strings are case insensitive

Bugfix: (PowerKiKi) Work Item GH-273 - ISTEXT() return wrong result if referencing an empty but formatted cell