Add "has" method to check if an instance has been created

Author: glen-84

index.js

@@ -46,6 +46,20 @@ module.exports.get = function (name) {
     throw new Error("An instance with the name `%s` was not found.".replace("%s", name));
 };
 
+/**
+ * Check if an instance has been created.
+ * @method has
+ * @param {String} name
+ * @returns {Boolean}
+ */
+module.exports.has = function (name) {
+    var instance = getSingle(name);
+    if (instance) {
+        return true;
+    }
+    return false;
+};
+
 /**
  * Start the Browsersync service. This will launch a server, proxy or start the snippet
  * mode depending on your use-case.