Improve setup.py and add the test command.

setup.py

@@ -1,7 +1,8 @@
 # -*- coding:utf-8 -*-
 
-from setuptools import setup, find_packages
 import sys
+from setuptools import setup, find_packages
+from sigal import __version__
 
 requires = ['PIL', 'jinja2', 'Markdown', 'clint']
 if sys.version_info < (2, 7):
@@ -11,20 +12,25 @@ entry_points = {
     'console_scripts': ['sigal = sigal:main']
 }
 
+with open('README.rst') as f:
+    README = f.read()
+
 setup(
     name='sigal',
-    version='0.1-dev',
+    version=__version__,
     url='https://github.com/saimn/sigal',
     license='MIT',
     author='Simon Conseil',
     author_email='contact@saimon.org',
     description='Simple static gallery generator',
-    long_description=open('README.rst').read(),
+    long_description=README,
     packages=find_packages(),
     zip_safe=False,
     include_package_data=True,
     platforms='any',
     install_requires=requires,
+    test_requires=['nose'],
+    test_suite='nose.collector',
     entry_points=entry_points,
     classifiers=[
         'Development Status :: 4 - Beta',