Added SVN logging observer.

It isn't triggered by anything yet. When the observer is called, it uses
Blinker to send out a signal for every [T12345] marker it sees in the
first line of each commit log. Those signals aren't connected to anything
yet.

NOTE: this requires the 'svn' Python module , which is a wrapper for the
'svn' commandline client. This client needs to be installed on our docker
when we deploy.

tests/logging_config.py

@@ -0,0 +1,26 @@
+LOGGING = {
+    'version': 1,
+    'formatters': {
+        'default': {'format': '%(asctime)-15s %(levelname)8s %(name)s %(message)s'}
+    },
+    'handlers': {
+        'console': {
+            'class': 'logging.StreamHandler',
+            'formatter': 'default',
+            'stream': 'ext://sys.stderr',
+        }
+    },
+    'loggers': {
+        'pillar': {'level': 'DEBUG'},
+        'attract_server': {'level': 'DEBUG'},
+        'werkzeug': {'level': 'INFO'},
+        'eve': {'level': 'WARNING'},
+        # 'requests': {'level': 'DEBUG'},
+    },
+    'root': {
+        'level': 'INFO',
+        'handlers': [
+            'console',
+        ],
+    }
+}