Docker image for osm-styles no longer available on docker Hub

[randomorder]

Following the guide in the README the user stumbles into an error due to a missing docker image:

docker pull geosolutionsit/geoserver:osm-styles-2.16.2-ny

Error response from daemon: manifest for geosolutionsit/geoserver:osm-styles-2.16.2-ny not found: manifest unknown: manifest unknown

[aaime]

Reference to sample docker image removed, that will avoid confusion amongst potential users.