Swift

- Exclude Expires header when max-age used
- Add Expires header as an independent option

- Added support for custom headers

- Added support for content-encoding option
- CLI also supports --content-encoding option

- Ensure connected on url getters `catalog, admin_url, upload_url, public_url, internal_url` (pull request 28)

- Added support for ssl_version configuration
- Command for object metadata. Available for cli (closes 16, 17)

- CLI now supports --no-cache which ignores the cached connection and removes the cache file if it exists (issue 12)
- Bugfix: invalidate nswift_cache when the connection fail (issue 27)
- Bugfix: OpenStruct in Ruby 1.9.x doesn't have the method [], using 'send' instead
- Bugfix: OpenStruct and nil doesn't have the method to_h in Ruby 1.9.x