fix __heartbeat__ so deep checks succeed when no dependencies are defined

lib/heartbeat.js

@@ -18,7 +18,7 @@ exports.setup = function(app, options, cb) {
 
   if (typeof options == 'function') {
     cb = options;
-  } else if (options) {
+  } else if (options && options.dependencies) {
     dependencies = options.dependencies;
   }
   var count = dependencies.length;
@@ -67,7 +67,7 @@ exports.setup = function(app, options, cb) {
     }
 
     // check all dependencies if deep
-    if (deep) {
+    if (deep && count) {
       for (var i = 0; i < count; i++) {
         check(dependencies[i] + exports.path, checkCB(i));
       }