Don't clear partitions on close
Don't clear partitions on close

Since partitions slice is not protected under a lock, setting it to
nil while closing causes a race if concurrent calls are accessing
the partitions slice elsewhere.  Since partitions do handle
concurrency and Open resets the slice, just leave it as it after
closing.

nooproblem/influxdb,nooproblem/influxdb,nooproblem/influxdb,linearb/influxdb,influxdb/influxdb,nooproblem/influxdb,mark-rushakoff/influxdb,mark-rushakoff/influxdb,linearb/influxdb,linearb/influxdb,linearb/influxdb,influxdb/influxdb,mark-rushakoff/influxdb,influxdata/influxdb,li-ang/influxdb,nooproblem/influxdb,li-ang/influxdb,linearb/influxdb,mark-rushakoff/influxdb,influxdata/influxdb,influxdb/influxdb,influxdb/influxdb,influxdb/influxdb,influxdb/influxdb,mark-rushakoff/influxdb,mark-rushakoff/influxdb