This commit removes the remaining bits of the fields index. In doing
so, the buildCursor method on the engine would need to be updated.
It turns out, that code was statically dead, so delete it and anything
that depended on it. Additionally, delete anything as reported by
the unused tool in the tsdb package.
We are moving the necessary code for 2.0 from the influxdb 1.X
repository to the platform 2.0 repository. The logger is an unnecessary
dependency on the old influxdb that is making life more complicated.
Jeff Wendling
zhulongcheng
Jonathan A. Sternberg
Edd Robinson