ZipArchive::extractTo bug 70350

Summary:Don't allow upward directory traversal when extracting zip archive files.

Files in zip files with `..` or starting at main root `/` should be normalized
to something where the file being extracted winds up within the directory or
a subdirectory where the actual extraction is taking place.

http://git.php.net/?p=php-src.git;a=commit;h=f9c2bf73adb2ede0a486b0db466c264f2b27e0bb

Reviewed By: FBNeal

Differential Revision: D2798452

fb-gh-sync-id: 844549c93e011d1e991bb322bf85822246b04e30
shipit-source-id: 844549c93e011d1e991bb322bf85822246b04e30