add Run via Docker instructions to documentation

    $ make test

### Run via Docker

To run FnordMetric Server using docker:

    $ sudo mkdir -p /var/lib/fnordmetric-data

    $ sudo docker run -p 8080:8080 -p 8125:8125/udp -v /var/lib/fnordmetric-data:/data/fnordmetric -t fnordmetric/fnordmetric-server

To build a Docker Image for FnordMetric Server, use the included dockerfile:

    $ git clone https://github.com/paulasmuth/fnordmetric.git && cd fnordmetric

    $ sudo docker -t myrepo/fnordmetric-server build .

### Binary Releases

_The first binary release will be published 2014-12-01_