Publish elasticsearch:5.6.10 to docker registry

[pavolloffay]

#44 bumped ES version from 5.5.2 to 5.6.10 but it's not available in docker registry.

When does https://github.com/CentOS/container-index rebuild the images?

Shouldn't be this line
https://github.com/CentOS/container-index/blob/master/index.d/rhsyseng.yaml#L98 changed to 5.6.10?

cc @ruromero

[mohammedzee1000]

PR merged, image should become available shortly :)

[TuranTimur]

any plan for uploading to docker registry?
registry.centos.org is very slow..