share/sharedb v8.0.0 on GitHub

#780 — 💥 BREAKING: Stop polling multi-channel queries every second by default
- A subscribed query with more than one channel used to default pollInterval to 1000, re-running against the database every second even when nothing had changed. It now has no interval by default, like a single-channel query. The pollDebounce default is unchanged
- Apps that already set pollInterval are unaffected. To restore the old interval, register this query middleware after the one that sets context.channels:
```
backend.use('query', (context, next) => {
  if (context.channels.length > 1) context.options.pollInterval = 1000
  next()
})
```