VOM: logging, populate and stats fixes

logging: allow a client to register a callback handler to recieve log messages
         that way the client can maintain a correctly sequenced log
populate: fix the creation of interface and the setting of the handle
stats: the reset promise idea is not defined behaviour.
       Use an eanble/disable command pair

Change-Id: I347720bb65df2874c7619e722d593bc863ee2bf1
Signed-off-by: Neale Ranns <neale.ranns@cisco.com>
diff --git a/src/vpp-api/vom/tap_interface_cmds.cpp b/src/vpp-api/vom/tap_interface_cmds.cpp
index 799b9af..b088560 100644
--- a/src/vpp-api/vom/tap_interface_cmds.cpp
+++ b/src/vpp-api/vom/tap_interface_cmds.cpp
@@ -112,7 +112,7 @@
 
   wait();
 
-  return rc_t::INPROGRESS;
+  return rc_t::OK;
 }
 
 std::string