Implement check of newer versions in the list command.

Also:
- Fix some errors not being emitted when a command failed.
- Update semver module; no need to check .valid against null.

lib/util/endpointParser.js

@@ -49,6 +49,23 @@ function json2decomposed(key, value) {
     return decompose(endpoint);
 }
 
+function decomposed2json(decEndpoint) {
+    var key = decEndpoint.name;
+    var value = '';
+    var ret = {};
+
+    if  (decEndpoint.source !== decEndpoint.name) {
+        value += decEndpoint.source + '#';
+    }
+
+    value += decEndpoint.target;
+
+    ret[key] = value;
+
+    return ret;
+}
+
 module.exports.decompose = decompose;
 module.exports.compose = compose;
 module.exports.json2decomposed = json2decomposed;
+module.exports.decomposed2json = decomposed2json;