I've just built (2015-04-14) a controller with odl-netconf-monitoring feature activated and after request /apidoc/apis I get :

"path": "/apidoc/apis/ietf-netconf-monitoring(2010-10-04)".

When I call a request /restconf/modules/module/ietf-netconf-monitoring/2010-10-04/schema I get this data :

<revision-date date="2010-09-24"></revision-date>.

In file in controller opendaylight/netconf/ietf-netconf-monitoring/src/main/yang/ietf-netconf-monitoring.yang are data :

import ietf-yang-types {
prefix yang;
revision-date "2010-09-24";
}