Simplegmail

New or Improved Features
- Close service explicitly in multithreaded download to avoid too many open sockets without garbage collection

New or Improved Features

- Add `noauth_local_webserver` flag to `Gmail` constructor
- Add `access_type` to `Gmail` constructor (though I believe Google returns refresh tokens regardless of whether offline or online is specified)
- Add `create_label` and `delete_label` functionality
- Add `cc` and `bcc` fields to `Message`
- Add the following query options: `list`, `in`, `delivered_to`, `category`, `larger`, `smaller`, `id`, `has`.

Bugfixes and Other Changes

- Fixed bug where attachment overwrite flag is used in the opposite way it was intended.

Bug fixes
- Refresh auth token upon expiry. If the token has expired during the program's run, it is now refreshed when the access to the service is attempted.

Bug Fixes and Other Changes
- Made check for email headers case insensitive

Bug Fixes and Other Changes

- Fixed error when using `sender="John Doe <john.doeemail.com>"` style sender addresses with `signature=True`.

New or Improved Features

- Message headers are now exposed as `Message.headers`, a dict from header name to value.