Add LiveQuery

src/LiveQuery/Id.js

@@ -0,0 +1,22 @@
+class Id {
+  className: string;
+  objectId: string;
+
+  constructor(className: string, objectId: string) {
+    this.className = className;
+    this.objectId = objectId;
+  }
+  toString(): string {
+    return this.className + ':' + this.objectId;
+  }
+
+  static fromString(str: string) {
+    var split = str.split(':');
+    if (split.length !== 2) {
+      throw new TypeError('Cannot create Id object from this string');
+    }
+    return new Id(split[0], split[1]);
+  }
+}
+
+module.exports = Id;