Log Message:
Update ruby-zip to 1.1.7.

1.1.7

* Fix UTF-8 support for comments
* Zip.sort_entries working for zip output
* Prevent tempfile path from being unlinked by garbage collection
* NTFS Extra Field (0x000a) support
* Use String#tr instead of String#gsub
* Ability to not show warning about incorrect date
* Be smarter about handling buffer file modes.
* Support for Traditional Encryption (ZipCrypto)