Bug 1484188

The following updates must be made to the Configuring Host Collections chapter in the Host Configuration Guide -

* Remove the current introduction to the chapter entirely, and create a new
  introduction that tells users what a host collection is and why they might
  want to create one.

  The following section of the upstream content contains a few details that can
  be used to create a new introduction, but not copied over as is -

  https://www.theforeman.org/plugins/katello/nightly/user_guide/host_collections/index.html

* Structure the sections in the chapter so that the top-level sections are 
  arranged in the following order -

  * Creating a Host Collection
  * Cloning a Host Collection
  * Removing a Host Collection
  * Adding a Host to a Host Collection
  * Removing a Host from a Host Collection
  * Adding Content to a Host Collection
  * Removing Content from a Host Collection
  * Changing the Life Cycle Environment or Content View of a Host Collection

  Note that the title of the section on adding hosts to host collections must
  be updated to that above.

* Remove the procedure on reviewing host collection details.