title: PouchDB sync cancel and restart
body: <p>I'm establishing sync (with event listeners) on application start and I need to stop it and run again. There is a .cancel() function that works, but how I can restart the sync? </p>
  
  <p>I've tried to delete object returned from sync() function after cancel() and run sync() again , but it sometimes raises a warning "pouchdb-6.1.2.min.js:7 (node) warning: possible EventEmitter memory leak detected. 11 listeners added. Use emitter.setMaxListeners() to increase limit.". As I get it, my old listeners are not removed by cancel(). </p>
  
  <p>How can I stop and start sync correctly?</p>