Expose Client Precision value

[nathanielc]

As it stands now when writing BatchPoints the precision does not default to the client's precision. See https://github.com/influxdb/influxdb/blob/master/client/influxdb.go#L226

Would it make sense to default bp.precision if empty to c.precision? Might be a breaking change in some cases :( Or we could just add a Client.Precision() method to return the precision and then use that when creating the BatchPoints object.

Thoughts?

[otoolep]

cc @sparrc

Cameron was in this code recently, there was significant resistance to breaking changes here.

[sparrc]

This is slightly different than what I was looking at, this doesn't seem like it would be a very breaking change. Unless someone was setting their client's precision to something other than ns and expecting it not to get applied?

[nathanielc]

@sparrc If you think its not a big change then I say we just default it. See #4361

[nathanielc]

closed by #4361