Openflow controller abstract connector

	- Add openflow_conn abstract impletation for all openflow connectors
	- Refactor all existing conenctor to Inherit la clase abstracta
	- Now all of connector raise an exeption in case of faliure
	- As OF_connector raise an expection, all code that make use of this class now capture the execption.
	- Add to ofc DB table last_error and status column
 	- Check for each operation if an error exist an update DB ofc status and last error column info

Change-Id: Ia3d3bf63fee79dd18d61aeeb08a983dfcb88b729
Signed-off-by: mirabal <leonardo.mirabal@altran.com>
diff --git a/openvim b/openvim
index cb7321d..58d6ff0 100755
--- a/openvim
+++ b/openvim
@@ -896,7 +896,7 @@
         if "ADMIN_PORT" not in vim_config:
             print "OPENVIM_ADMIN_PORT variable not defined"
             return 401 # HTTP_Unauthorized
-        url = "http://%s:%s/openvim/networks/openflow/clear" %(vim_config["HOST"], vim_config["ADMIN_PORT"])
+        url = "http://%s:%s/openvim/networks/clear/openflow" %(vim_config["HOST"], vim_config["ADMIN_PORT"])
         r,c = vim_delete(url)
     else:
         return 400 #HTTP_Bad_Request