Fixed #1623. Added 'MD5-sess' algorithm to HTTPDigestAuth
fixed extra bonus bug
Fixed #1630, added test case for cookie persistence.
checkout auth
Fixed #1630
Don't send the full URL on CONNECT messages.
Correctly lowercase a redirect scheme.
added param to cookiejar_from_dict instead of creating new method.
add myself to authors.
Accept per-file headers in multipart file POST messages.

- Each file in the `files` argument can now be a 4-tuple, instead of
  just a file, 2-tuple, or 3-tuple. If it is, the last value in the
  tuple is a dictionary of extra headers.
Minor doc updates

- Improve wording of sentence describing proxy environment
  variable setting.
- Mention that proxy URLs must include the scheme.
Translate urllib3 ProxyError into a requests ProxyError derived from ConnectionError.
Merge pull request #1651 from GrahamDumpleton/master

Translate urllib3 ProxyError into a requests ProxyError derived from ConnectionError.
Merge pull request #1649 from dpursehouse/minor-doc-updates

Minor doc updates
replaced deprecated BaseException
updated print statement
fixed print statement
fixed print statement
removed deprecated while 1:
Update advanced.rst