Windows has a problem with some of the php:// I/O streams in this library, which this update addresses.
ISLANDORA-83 Instead of PHP_OS, now using php_uname() for OS detection.
ISLANDORA-83 Added function to handle Windows detection.
ISLANDORA-83 'isWindows' function is now protected. Edited comments.
Merge pull request #83 from slangerx/1.x

Windows-compatibility: Problems with php:// I/O streams