fix Headers.__setitem__ to correctly accept slices
WIP
Add testcase
Fixing the rest of the http tests
More fixes
Fixed http testsuite
More fixes for http
Fixed some ambiguous literals
__nonzero__ => __bool__
Merge pull request #331 from untitaker/sprint-branch

:>
Fixed to adapt to new signature of to_bytes
Merge pull request #332 from untitaker/sprint-branch

Fixed to adapt to new signature of to_bytes
Remove from six import next