Move marconi.common.Kernel to marconi.Kernel.

marconi.common should contain commonly importable utilities.
But Kernel depends on things outside marconi.common, which
results in a recursive dependency if they import anything under
marconi.common.

Change-Id: Ibfeb5abe9fc21a8bcf170d1eddceac44e5abf844

bin/marconi-self-host

@@ -28,7 +28,8 @@ kernel with the WSGI transport and export the WSGI app callable, e.g.:
 """
 
 import logging.config
-from marconi.common import Kernel
+
+import marconi
 
 
 if __name__ == '__main__':
@@ -37,5 +38,5 @@ if __name__ == '__main__':
     config_file = '/etc/marconi/marconi.conf'
 
     logging.config.fileConfig(logging_config_file)
-    kernel = Kernel(config_file)
+    kernel = marconi.Kernel(config_file)
     kernel.run()

marconi/__init__.py

@@ -13,6 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from marconi.kernel import Kernel
 import marconi.version
 
 __version__ = marconi.version.version_info.deferred_version_string()

marconi/common/__init__.py

@@ -1,3 +1 @@
-"""Code common to Marconi, including main application logic."""
+"""Code common to Marconi"""
-
-from .kernel import Kernel  # NOQA

marconi/tests/test_simple.py

@@ -12,8 +12,8 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-import marconi.tests.util as util
+import marconi
-import marconi.common
+from marconi.tests import util
 
 
 class TestSimple(util.TestSuite):
@@ -21,7 +21,7 @@ class TestSimple(util.TestSuite):
     def test_simple(self):
         """Doesn't really test much"""
         conf_file = self.conf_path('wsgi_reference.conf')
-        kernel = marconi.common.Kernel(conf_file)
+        kernel = marconi.Kernel(conf_file)
         transport = kernel.transport
         wsgi_app = transport.app
         self.assertTrue(True)