Docker support for cache server

[nicoloboschi]

JIRA: https://dev.blazingcache.org/jira/browse/BLAZ-55

Reporter: eolivelli @eolivelli

Provide an official image for Docker

Comments from JIRA

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Enrico Olivelli 2016-12-27T16:40:59.000+0100

see https://github.com/docker-library/official-images for instructions

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Enrico Olivelli 2016-12-27T16:45:07.000+0100

[~caio] do you want to pick up this issue ?