Merge pull request #1 from rajbot/master

Allow users to import the module and access item metadata without having to supply IA credentials.
Merge pull request #2 from rajbot/master

Add archive.File class and test cases
Merge pull request #3 from rajbot/master

Add readme
Merge pull request #4 from rajbot/master

Add item.download()
Updated modify_metadata() to use httplib instead of the requests lib. As well as a lot of cleaning up.
Added the missing and required parameter, "metadata" to modify_metadata()
Renamed library from archive to internetarchive
Updated README with new library name, "internetarchive"
removed api.py
Removed "headers" and "error_message" from dict returned by Item.modify_metadata()
Cleaned up mutlipart upload code. Also removed parallel multipart uploads functionality as parallelization should always take place at the item level, not the partlevel)
Added link to blog post explaining what exactly an Archive.org "item" is, and how they are structured
Added support in Item.download() for downloading only specific formats
Update uploading docs.