align PEAR_FILE_PACKAGE Pattern to PEAR version regex:

http://pear.php.net/reference/PEAR-1.3.3.1/PEAR/_PEAR-1.3.3.1_PEAR_Common_php.html
(search for: _PEAR_COMMON_PACKAGE_VERSION_PREG)
Merge pull request #1 from CansaSCityShuffle/master

align PEAR_FILE_PACKAGE Pattern to PEAR version regex: