started working on this with the idea of fixing #1623, although I
realized that this was actually just a documentation issue around
a toml eccentricity.
closes#1623
Adding precision rounding to the accumulator. This means that now every
input metric will get rounded at collection, rather than at write (and
only for the influxdb output).
This feature is disabled for service inputs, because service inputs
should be in control of their own timestamps & precisions.
Cameron Sparr
Patrick Hemmer