Improve Python 3.x compatibility

Some mechanical translation of the deprecated
except x,y construct. Should work with Python >= 2.6
just fine

Change-Id: I394f9956b9e3e3d9f5f1e9ad50c35b13200af2a1

glanceclient/shell.py

@@ -470,6 +470,6 @@ def main():
     except KeyboardInterrupt:
         print >> sys.stderr, '... terminating glance client'
         sys.exit(1)
-    except Exception, e:
+    except Exception as e:
         print >> sys.stderr, e
         sys.exit(1)