fix flakes and pep8 errors
Merge pull request #100 from pkit/tests_fixes

fix flakes and pep8 errors
prepare for freeform REST services

this patch generalizes `version` part of url into REST interface version
it also adds ability to place version in `X-Zerovm-Execute` header

Example:

`GET /open/account/container/obj` == `GET /v1/account/container/obj` + `X-Zerovm-Execute: open/1.0`
fix bug with wildcard matching single object

when wildcard in the `swift://` path was matching only single object some strange things happened
Merge pull request #99 from pkit/before_queue

fix bug with wildcard matching single object
Merge pull request #98 from pkit/open

prepare for freeform REST services
implement task scheduler

fix queue issues

add null object server implemenation

null server does not store any objects
it only uses regular PUT/DELETE code paths to update container server about object listings directly

designed for use in storage policies that store some metadata only, not objects themselves

GET, HEAD and POST are forbidden

added more tests to queue

now added better test suite for queue middleware
tests the queue with object server and null object server

reafactor common methods into QueueClient

split queue manipulation functionality into QueueClient class, used by both SchedulerMiddleware and QueueMiddleware

add scheduler