influxdb 1.x env variables cleanup

https://docs.influxdata.com/influxdb/v1.8/administration/config/

These options are missing (might be new in 1.8.1):
http.flux-log-enabled
http.prom-read-auth-enabled
http.headers
graphite.tags
graphite.templates

The following config options are missing env variables:
https://docs.influxdata.com/influxdb/v1.8/administration/config/#validate-keys-false
https://docs.influxdata.com/influxdb/v1.8/administration/config/#suppress-write-log-false
https://docs.influxdata.com/influxdb/v1.8/administration/config/#parse-multivalue-plugin-split

These env variables seem like they are missing an `_0_`
https://docs.influxdata.com/influxdb/v1.8/administration/config/#bind-address-4242
https://docs.influxdata.com/influxdb/v1.8/administration/config/#database-opentsdb
https://docs.influxdata.com/influxdb/v1.8/administration/config/#retention-policy-2
https://docs.influxdata.com/influxdb/v1.8/administration/config/#consistency-level-one-1
https://docs.influxdata.com/influxdb/v1.8/administration/config/#tls-enabled-false
https://docs.influxdata.com/influxdb/v1.8/administration/config/#certificate-etc-ssl-influxdb-pem

https://docs.influxdata.com/influxdb/v1.8/administration/config/#bind-address-8089
https://docs.influxdata.com/influxdb/v1.8/administration/config/#database-udp
https://docs.influxdata.com/influxdb/v1.8/administration/config/#retention-policy-3
https://docs.influxdata.com/influxdb/v1.8/administration/config/#batch-timeout-1s-2
https://docs.influxdata.com/influxdb/v1.8/administration/config/#read-buffer-0-1
https://docs.influxdata.com/influxdb/v1.8/administration/config/#precision

This env variable looks incorrect:
https://docs.influxdata.com/influxdb/v1.8/administration/config/#read-buffer-0-1