Work toward Python 3.4 support and testing

Change-Id: Ic4e5af990d5a3dc85de2f90ea41189cb4a5d99fa
Add check for makemessages in tox.ini PEP8

This commit adds a check of extracting message catalogs to
tox PEP8 check. It is useful to avoid a bug like bug 1379054.

It also fixes a warning "WARNING:root:No local_settings file found."
in run_tests.sh --makemessages and --compilemessages by specifying
Django settings.

Closes-Bug: #1379507

Change-Id: I5541e28a87d48601202bf8180a18eadb5a91770b
Sync oslo-incubator for fileutils, log and policy

Sync from oslo-incubator commit 4504e4f4917d99c4889a8a5b7907d6b23ced2ffc

Additional changes:
- remove excutils since this already moved to oslo-utils
- added _i18n.py workaround from oslo-incubator, required while transitioning
to oslo.i18n
- fix openstack_dashboard/policy.py to work with latest policy code

Change-Id: I904b9af517cc85e0cc041a1467d6fda599d8d3a1
Partially-Implements: blueprint improve-oslo-usage
Migrate jsonutils to oslo.serializer.jsonutils

Removing the local copy since we are now referecning the code in
oslo.serializer.

Change-Id: I86fbef479777c38fe4d3e5aad99595371c404988
Partially-Implements: blueprint improve-oslo-usage
Use strutils from oslo.utils

Rather than sync'ing with oslo-incubator, let's use the library
oslo.utils instead. Removing the local copy of strutils.

With removal of strutils in local, gettextutils is now safe to
remove as well.

Change-Id: I0d98d41b03d105e34933efcdb5c60020141e13fb
Partially-Implements: blueprint improve-oslo-usage
Merge "Sync oslo-incubator for fileutils, log and policy"
Merge "Migrate jsonutils to oslo.serializer.jsonutils"
Merge "Use strutils from oslo.utils"
Merge "Work toward Python 3.4 support and testing"
Merge "Add check for makemessages in tox.ini PEP8"