Merge pull request #31 from davidjb/master

Update default debug setting documentation and how debug level is handled
pep8
pep8
Fix messages with both HTML and plain text bodies that also have attachments:

Closes #32.  Note that, as opposed to the issue description, per
RFC2046 the HTML part should be last inside the multipart/alternative.
pep8
Squash some Python 3 deprecation warnings
Allow setting Content-Transfer-Encoding for body and html via Attachments:

Be warned that this may not work for utf-8 on some versions of Python
because of a bug in email.quiprimime: http://bugs.python.org/issue16948

Closes #29
prep for 0.11
back to dev
Add CONTRIBUTORS.txt file, overlooked in inital repo creation.
Add myself to contributors
contributors += Dan Connolly
Merge pull request #36 from dckc/master

contributors += me
sign contributors.txt
adjust for reality:
Update CONTRIBUTORS.txt

added myself to contributors
Merge pull request #37 from marcinkuzminski/patch-1

Update CONTRIBUTORS.txt
Sign CONTRIBUTORS.txt
Merge pull request #38 from t2y/master

Signed CONTRIBUTORS.txt
update contributors