config.yang file conflict between snmp4sdn feature and controller config subsytem.

config.yang in snmp4sdn feature

module config {
yang-version 1;
namespace "urn:opendaylight:snmp4sdn:md:config";
prefix config;

organization "Industrial Technology Research Institute of Taiwan";
contact "Yi-Ling Hsieh <ylhsieh@itri.org.tw>";

description "YANG version of the SNMP4SDN Config Service MIB.";

revision "2014-08-15"

{//TODO: update date description "SNMP4SDN Config Service"; }

。。。
}

config.yang in config substem
module config {
yang-version 1;
namespace "urn:opendaylight:params:xml:ns:yang:controller:config";
prefix "config";

description
"This module contains the base YANG definitions for NS-OS
configuration subsystem. The system modeled revolves around two
major concepts: modules and services.";

revision "2013-04-05"

{ description "Reworked to give modules their own space."; }

。。。。

}

the two yang files module name are the same, after installing snmp4sdn,

when configing services and modules configuration , exception occurs because of the module name overriding.

config.yang file in snmp4sdn should be changed to other module name to solve this bug.

besides there are a few minor bugs in other yang files's prefix field:
fdb.yang
topology.yang

Excuse my poor English, Thanks.