Move EIP-2159 to last call (#2231)

* Add common metrics EIP.

* Fix spelling error.

* Assign EIP number, added more information on what Prometheus does.

* Add link to prometheus website for further info.

* Fix link.

* Fix discussion link.

* Switch to standards track - interface instead of informational.

* Add motivation.

* Link to PR implementing EIP in Pantheon.

* Move EIP-2159 to last call.

* Add review period end

EIPS/eip-2159.md

@@ -3,7 +3,8 @@ eip: 2159
 title: Common Prometheus Metrics Names for Clients
 author: Adrian Sutton (@ajsutton)
 discussions-to: https://ethereum-magicians.org/t/common-chain-metrics/3415
-status: Draft
+status: Last Call
+review-period-end: 2019-08-31
 type: Standards Track
 category: Interface
 created: 2019-07-01
@@ -55,7 +56,7 @@ Clients may already be publishing these metrics using different names and changi
 
 ## Implementation
 <!--The implementations must be completed before any EIP is given status "Final", but it need not be completed before the EIP is accepted. While there is merit to the approach of reaching consensus on the specification and rationale before writing code, the principle of "rough consensus and running code" is still useful when it comes to resolving many discussions of API details.-->
-These metrics are currently captured by [Pantheon](https://pegasys.tech) under `pantheon_` prefixed names. It is planned that they will be renamed to match this EIP in the next release ([see PR](https://github.com/PegaSysEng/pantheon/pull/1634)).
+[Pantheon](https://pegasys.tech) switched to using these standard metric names in its 1.2 release ([see PR](https://github.com/PegaSysEng/pantheon/pull/1634)).
 
 ## Copyright
 Copyright and related rights waived via [CC0](https://creativecommons.org/publicdomain/zero/1.0/).