I have duplicated content in 3 places in the `website/` directory. We need to have one place for the real content and replace the dups with redirect to the actual content. This looks like is may be true for several other pages and honestly I'm not sure if they are all needed but there are many links out in the wild that point to the old path for the CCO recommender pages so we should do this for the ones below at least. Better yet we may want to clean out any other dups unless someone knows why not.
Dups to be replaced with redirects to the above content. I vaguely remember all these different site structures so there may be links to them in the wild.
mahout/website/recommender-overview.md => mahout/website/docs/latest/algorithms/recommenders/index.md
mahout/website/users/algorithms/intro-cooccurrence-spark.md => mahout/website/docs/latest/algorithms/recommenders/cco.md
mahout/website/users/recommender/quickstart.md => mahout/website/docs/latest/algorithms/recommenders/index.md
mahout/website/users/recommender/intro-cooccurrence-spark.md => mahout/website/docs/latest/algorithms/recommenders/cco.md