fixes #2380

closes #2390
closes #2404

fixes #2282

The docker engine-api package we use needs golang 1.7+, see:
https://github.com/docker/engine-api/pull/382#issuecomment-244512952

So telegraf won't compile without 1.7

closes #2339

Also, ensure pidfile perms are 644

closes #1516 
closes #1711 
closes #1721 
closes #1526 

* Procstat: don't cache PIDs

Changed the procstat input plugin to not cache PIDs. Solves #1636.
The logic of creating a process by pid was moved from `procstat.go` to
`spec_processor.go`.

* Procstat: go fmt

* procstat: modify changelog for #2206

closes #2244
closes #1547

this defer function was causing telegraf to call os.Exit(0) instead of
panicking when it was supposed to.

closes #2341

closes #2356

* ceph: maps are already refs, no need to use a pointer

* ceph: pgmap_states are represented in a single metric "count", differenciated by tag

* Update CHANGELOG

* Update README.md

* Add lock support to the IPtables input plugin

* Update iptables.go

Doc cleaning

* Add in support for looking for substring in response

* Add note to CHANGELOG.md

* Switch from substring match to regex match

* Requested code changes

* Make requested changes and refactor to avoid nested if-else.

* Convert tabs to space and compile regex once

* Keep -config-directory when running as Windows service

* Update changelog

* Make Logparser Plugin Check For New Files

Check in the Gather metric to see if any new files matching the glob
have appeared. If so, start tailing them from the beginning.

* changelog update for #2141

closes #2324

fixes #2317