Update null log handling for py26

Python 2.6 does not have a NullHandler in the logging
module, so introduce a little class that does the same
work.

Also add __all__ to the package init so extra names are
not exported.

Resolves issue #2

Change-Id: Id59d394cd02372e2c31de336894f06653cb1e22d
Merge pull request #26 from dhellmann/bug/logging-py26

Update null log handling for py26
prep for release 0.11

Change-Id: If291824f46cf8ab48c25cca54fbb072aad65cf4c
Fixes reporting the error when drivers have the same name

Resolves issue #25

Change-Id: I944800fc2da0018b5b3bb076d296c38126fe97bf
Add map_method function to managers

This allows to use map() directly over some extension method in a more
convenient way. It's a pattern we often need, so let's built it directly
in Stevedore.
Merge pull request #27 from jd/master

Add map_method function to managers
Fix flake8 failures from pull/27

Fix a few formatting issues from within the
previous pull request.

Change-Id: Iadb0d5d4bfa1ac460c730e8af0cfec9386a4c066
Switch to pbr

Resolves issue #16
Merge pull request #28 from jd/jd/pbr

Switch to pbr
remove version from setup.cfg and rely on git tag

Change-Id: Ib30d0538f4d17a8890a0001a4d0116b08dd74868
update history and announce file for release

Change-Id: I830d1755c9ed8dbf356edaf68243a01b1d6eb6ac
fix version number in blog announcement file

Change-Id: Ieac1a09728f2a62d5c5c372b78bf6ad480688eb9
Fix pip call in tox config

Tox passes --pre to pip, which means we get pre-release
versions of stuff. That breaks the docs build, but is
just a bad idea anyway, so override the setting so we
don't do it.

Change-Id: Iec89b12a969f34486005e8dc41cb189438b38959
add pypy to default test env list

Change-Id: I1fba36e54850c18fdb2720377566ad43ee5b8661
add pypy to travis config

Change-Id: Ib4b9b5a91b7cfce8241b7ad641bb0b959344dc2a
use item access instead of temporary dict when ordering extensions
add test instance factory for the base, named, and hook managers

The class method make_test_instance constructs manager instances using a
predefined list of extensions, rather than loading from entry points.
fix a reference bug when DriverManager finds multiple entry points
enabled extension manager test instance factory
driver extension manager test instance factory