temp revert #81

This patch introduce a breaking change in rrweb-record's API, so
we will revert it in 0.7.x and release it in 0.8.

typings/record/index.d.ts

@@ -1,4 +1,3 @@
 import { recordOptions, listenerHandler } from '../types';
-export declare function addCustomEvent<T>(tag: string, payload: T): void;
 declare function record(options?: recordOptions): listenerHandler | undefined;
 export default record;