Added bytes_range option by default to lib/storage.stream_read
Added global options for storage plugins to implement bytes range
Implemented byte-range support on the local storage backend + unit tests
Implemented bytes range in boto_*
Serve Accept-Ranges header when needed
Parse bytes range in incoming request and pass right args to the storage lib
Implement range headers parsing + fix unit tests
Merge pull request #221 from dotcloud/bytes-range

Bytes range