Set keystonemiddleware and routes.middleware to log on WARN level

Thanks to I49a82c5b3446784d254ca558f51b6c3e5c2028eb, we can augment
oslo's set of default log levels with project specific ones.

Add keystonemiddleware as warn level since its verbose and nova isn't
trying to debug keystonemiddleware.

Add routes.middleware since this generates 3 log entries per API request
and doesn't help make debugging easier.

Change-Id: I4b762eea922fe358ed2d0ac409b3caecced6ec96
Use index-filter instead of tree-filter in graduate.sh

tree-filter causes git-filter-branch to checkout current tree for every
commit. That's rather IO-expensive operation. Given that tree-filter
runs "git rm" for every unneeded file, IO load becomes even higher.

With this change graduate.sh becomes less IO-bound and so runs way
faster (over 10x faster on my machine, even with tmpfs).

Change-Id: I3f08a3ac9a7f99a22b58c0c8017a53f4420fdcc3
log: make tests portable

There's no need to specify the address of the logger, and it actually
breaks the portability of the tests. With this patch, the tests also
work on Darwin.

Change-Id: Iae3fae1e089fd6ea03ac078a093f0c80a2988788
Except socket.error if syslog isn't running

When setting `use_syslog=true` and restarting the service, if syslog (or
rsyslog) isn't running, except the error and inform the user instead
of failing with a generic Errno 111.

Change-Id: Ie4ce3e84dcff838b569d6e2711aee5ea21c01083
Partial-Bug: 1328501
Correct coercion of logged message to unicode

Changed to check if logged message is an instance of six.text_type
and coerce it to unicode if it isn't.

Change-Id: I26b0d3490f731f6fdb9a429aa9ef59360ddc88ba
Closes-bug: #1348244
Add unicode coercion of logged messages to ContextFormatter

The ContextAdapter is being retired as part of
blueprint remove-context-adapter so any processing in the
ContextAdapter needs to be added to the ContextFormatter.

Coercion in the ContextAdapter was fixed as part
of change-id: I26b0d3490f731f6fdb9a429aa9ef59360ddc88ba

Partially implements blueprint remove-context-adapter

Change-Id: Icf4533074b45623983f4e3eeb7e1a1ae618bf605
Enhance versionutils.deprecated to work with classes

If object being decorated is a function, it is processed as before,
otherwise a new class is created which logs deprecated message when
class is instantiated. This change comes with 2 unit tests.

Closes-Bug: #1337889
Change-Id: Ib5cc04bea0ff2ea588618599f4e42df16cb85a0d
Merge "Use index-filter instead of tree-filter in graduate.sh"
Merge "Enhance versionutils.deprecated to work with classes"
Merge "Correct coercion of logged message to unicode"
Merge "Add unicode coercion of logged messages to ContextFormatter"
Merge "log: make tests portable"
Merge "Except socket.error if syslog isn't running"
Merge "Set keystonemiddleware and routes.middleware to log on WARN level"