Add the aws-health-exporter to the list of exporters.

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PromCon 2017 recap blog post

I've updated the NATS Exporter to be the one maintained by the NATS team, which was released this week. The previous link was to Lovoo's exporter - Markus (maintainer of Lovoo's) is aware of this change and fine with it.

Signed-off-by: Sylvain Rabot <sylvain@abstraction.fr>

* extended the Naemon exporter with Nagios

* changed order

This was https://github.com/prometheus/docs/pull/330

Add speedtest exporter (golang)

Update link for FreeBSD kernel exposition

as discussed in #811, the manpage is core documentation for BSDs. Link it instead of the discussion around adding this.

/cc @RichiH

* added reference to mssql exporter

* renamed exporter to MSSQL as recommended by brian-brazil

Document that alerts can inhibit themselves

Document that FreeBSD now ships with the prometheus_sysctl_exporter(8) daemon
which will exposes sysctl values from the kernel in Prometheus's format.

* Added Hadoop HDFS FSImage exporter to list of storage exporters

* Sorted storage exporters by name

* clarify gce sd config when meta data is returning urls as values

* examples has been removed

update copyright year

move development mailing list info to Contributing section

The version expressed by the AlertManager was changed in the following
commit: 
  https://github.com/prometheus/alertmanager/commit/3269bc39e121452abdce24db1d3d9003d99184d1

This updates the documentation to reflect that change. 

* Suffix the groupKey with a `,` character

`2 * 3 ^ 2` being equivalent to `2 * (3 ^ 2)` doesn't actually demonstrate that `^` is right associative. It just follows from operator precedence. The significance of right associativity is better exemplified by something of same precedence level as `^`.