VOL-1437 : Fix display of devices in CLI

Renamed state field in image download proto which caused
json marshalling to fail.

other updates
- unmarshal data properly when pulling data from kv in watch
- do not update unecessarily if watch data matches data in memory
- added ofagent target to python Makefile
- fixed grpc path to update log level which interfered with getdevice

Change-Id: I4fceeb539c3325b6754efe2b68251d83b7367211
diff --git a/protos/device.proto b/protos/device.proto
index 902a58c..0770060 100644
--- a/protos/device.proto
+++ b/protos/device.proto
@@ -144,7 +144,7 @@
     uint32 crc = 4;
 
     // Download state
-    ImageDownloadState state = 5;
+    ImageDownloadState download_state = 5;
 
     // Downloaded version
     string image_version = 6;
diff --git a/protos/voltha.proto b/protos/voltha.proto
index faf57a1..fdff7f6 100644
--- a/protos/voltha.proto
+++ b/protos/voltha.proto
@@ -146,7 +146,7 @@
     // Get more information on a given physical device
     rpc UpdateLogLevel(Logging) returns(google.protobuf.Empty) {
         option (google.api.http) = {
-            get: "/api/v1/devices/{id}"
+            get: "/api/v1/logs"
         };
     }