Fixed tox
Update requirements: add futures. Update MANIFEST.in

[ci skip]
[compatibility] 2.6: sys.version_info is ordinary tuple, not named
[CI] Fixed tox again [ci skip]
Move exceptions for tools from v0.11
Add decorators package. Put @coroutine into it.
Channel with rx, tx properties is returnde

instead of (rx, tx) pair to make *wait() easier.
Sorted detail.service out.

* Move exceptions related to services from detail to cocain.exceptions.
* CocaineIO to io
Add CocaineErrno [skip ci]
Just stole 1000th commit [skip ci]
Push EmptyResponse instead of raising ChokeEvent

in case of `close` event to make choke-only methods convenient.
[skip ci] travis for master is temporarily disabled
pep8
Add base exception: CocaineError
Welcome, Worker!
[ASIO] Service connects using tuple of endpoints
[Service] Handling dispatch tree is adopted to a new two-values format
[Worker] Tiny fixes. Added test for worker
[Worker] Coverage and typo fixe
[Logger] Add logger class