Fix bug 659: Don't use static member variables

This fixes bug 659, where static member variables were used by the
VCAMonitor, causing unexpected behaviour when deploying and destroying a
network service multiple times.

Change-Id: Icc5e4da62aeb11e4c89ba3cf5f148c6959acf7e3
Signed-off-by: Adam Israel <adam.israel@canonical.com>
diff --git a/n2vc/vnf.py b/n2vc/vnf.py
index 1bdfe2f..a486f27 100644
--- a/n2vc/vnf.py
+++ b/n2vc/vnf.py
@@ -57,13 +57,12 @@
 class VCAMonitor(ModelObserver):
     """Monitor state changes within the Juju Model."""
     log = None
-    ns_name = None
-    applications = {}
 
     def __init__(self, ns_name):
         self.log = logging.getLogger(__name__)
 
         self.ns_name = ns_name
+        self.applications = {}
 
     def AddApplication(self, application_name, callback, *callback_args):
         if application_name not in self.applications: