This commit deletes most of the code to service reads from influxdb
and pulls it in from platform instead.
Of note, the models.Tag and models.Tags types are now aliases to the
platform models.Tag and models.Tags types. Additionally, many types
in the tsdb package relating to cursors are also aliases to the same
types in the platform cursors package.
This updates the platform and flux repos to the current master in the
Gopkg.lock.
69dc031a75