Support building wheels (PEP-427)

With that, building and uploading wheels to PyPI is only one "python
setup.py bdist_wheel" away.

Also, changes LC_ALL from C to UTF-8 to get around a bug in pip:

https://github.com/pypa/pip/issues/761

Change-Id: I508ab6436c29b23f6b8d56c0ec63eb26f3568819

setup.cfg

@@ -49,3 +49,6 @@ output_file = solum/locale/solum.pot
 [entry_points]
 console_scripts =
     solum-api = solum.cmd.api:main
+
+[wheel]
+universal = 1

tox.ini

@@ -10,7 +10,7 @@ setenv =
    VIRTUAL_ENV={envdir}
    LANG=en_US.UTF-8
    LANGUAGE=en_US:en
-   LC_ALL=C
+   LC_ALL=en_US.UTF-8
 deps = -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
 commands = python setup.py testr --slowest --testr-args='{posargs}'
@@ -27,4 +27,4 @@ commands = python setup.py testr --coverage --testr-args='{posargs}'
 [flake8]
 show-source = True
 builtins = _
-exclude=.venv,.git,.tox,dist,doc,*openstack/common*,*lib/python*,*egg,build
+exclude=.venv,.git,.tox,dist,doc,*openstack/common*,*lib/python*,*egg,build