Make options instance more dict-like.
options[key] should return a value, not an _Option instance
Replace options.as_dict() with group_dict()
stack_context deactivation support
Unnecessary import removed
Parameter is no longer necessary
Send HTTP 200 in response to Range: bytes=0-
Merge master
Note about conditional return of HTTP 206
Only send Content-Range with HTTP 206
Merge pull request #794 from wolever/accept-range-in-static-file-handler

Send HTTP 200 in response to `Range: bytes=0-`
Test revealing StaticFileHandler path regression.

A bisect suggests that the regression was introduced in
3f04edf5546e388293d8d1d2f015ca74f8a93217
OptionParser.group_dict() now requires a group. Add as_dict().
Merge pull request #789 from ajdavis/opts-enhancements

Make options instance more dict-like.
fixed bugs
Fix a dangling doc reference, and add a doc check to tox and travis.
Actually install sphinx on travis; fix directory reference.
$TMPDIR isn't set on travis-ci.
Fix regression in async prepare: don't continue of prepare called finish.
Backport changes from ssl.match_hostname in Python 3.3.

Includes two commits:
* Fix potential CPU DoS via abusive wildcard pattern
  http://hg.python.org/cpython/rev/fafd33db6ff6
* Fall back to common name when SAN doesn't contain any DNS names
  http://hg.python.org/cpython/rev/1b37827984ba

Closes #799.