feat(agent): add agent support (#1828)

app/agent/services/agentService.js

@@ -0,0 +1,24 @@
+angular.module('portainer.agent')
+.factory('AgentService', ['$q', 'Agent', function AgentServiceFactory($q, Agent) {
+  'use strict';
+  var service = {};
+
+  service.agents = function() {
+    var deferred = $q.defer();
+
+    Agent.query({}).$promise
+    .then(function success(data) {
+      var agents = data.map(function (item) {
+        return new AgentViewModel(item);
+      });
+      deferred.resolve(agents);
+    })
+    .catch(function error(err) {
+      deferred.reject({ msg: 'Unable to retrieve agents', err: err });
+    });
+
+    return deferred.promise;
+  };
+
+  return service;
+}]);