async remove (torrentId, opts, cb) {
    if (typeof opts === 'function') return this.remove(torrentId, null, opts)

    this._debug('remove')
    const torrent = await this.get(torrentId)
    if (!torrent) throw new Error(`No torrent with id ${torrentId}`)
    this._remove(torrent, opts, cb)
  }
Remove a torrent from the client.
@param  {string|Buffer|Torrent}   torrentId
@param  {function} cb