Use babel to generate translation file

Fixes bug 1103519

Following http://wiki.openstack.org/Translations to integrate transifex
translation into quantum

We added the empty file quantum/locale/quantum.pot to avoid the
failure of the Jenkin's translation-jobs because git doesn't allow empty
directory to be added into the repository.

After this patch accepted, we need to do as below:
1. Make the transifex quantum project
(https://www.transifex.com/projects/p/quantum/) as part of the
openstack transifex project hub and give access to the transifex
openstack Jenkins account.

2. Add the translation-jobs into openstack/openstack-ci-puppet for
ceilometer.

Change-Id: I329a8bdc51ed8a0e75399c592d3991b1ec06a855

.gitignore

@@ -15,3 +15,4 @@ run_tests.log
 setuptools*.egg/
 .tox/
 .venv/
+*.mo

MANIFEST.in

@@ -5,6 +5,7 @@ include quantum/db/migration/README
 include quantum/db/migration/alembic.ini
 include quantum/db/migration/alembic/script.py.mako
 include quantum/db/migration/alembic/versions/README
+recursive-include quantum/locale *
 
 exclude .gitignore
 exclude .gitreview

babel.cfg

@@ -0,0 +1,2 @@
+[python: **.py]
+

setup.cfg

@@ -14,3 +14,18 @@ cover-package = quantum
 cover-html = true
 cover-erase = true
 where=quantum/tests/unit
+
+[extract_messages]
+keywords = _ gettext ngettext l_ lazy_gettext
+mapping_file = babel.cfg
+output_file = quantum/locale/quantum.pot
+
+[compile_catalog]
+directory = quantum/locale
+domain = quantum
+
+[update_catalog]
+domain = quantum
+output_dir = quantum/locale
+input_file = quantum/locale/quantum.pot
+

tools/test-requires

@@ -1,3 +1,4 @@
+Babel>=0.9.6
 cliff
 coverage
 distribute>=0.6.24