Let Main Server emit startup notice including version

There was no place in the software telling the user the
version in use. So start by having the main server emit a
startup notice including the version string. Uses python
logging, so should be easy to reconfigure, etc.

mediagoblin/app.py

@@ -16,11 +16,12 @@
 
 import os
 import urllib
+import logging
 
 import routes
 from webob import Request, exc
 
-from mediagoblin import routing, meddleware
+from mediagoblin import routing, meddleware, __version__
 from mediagoblin.tools import common, translate, template
 from mediagoblin.tools.response import render_404
 from mediagoblin.tools import request as mg_request
@@ -31,6 +32,9 @@ from mediagoblin.init import (get_jinja_loader, get_staticdirector,
     setup_storage, setup_beaker_cache)
 
 
+_log = logging.getLogger(__name__)
+
+
 class MediaGoblinApp(object):
     """
     WSGI application of MediaGoblin
@@ -47,6 +51,7 @@ class MediaGoblinApp(object):
            (Note: setting 'celery_setup_elsewhere' also disables
            setting up celery.)
         """
+        _log.info("GNU MediaGoblin %s main server starting", __version__)
         ##############
         # Setup config
         ##############