Not adding internal redirects because these pages are so new.

Based on discussion here:
https://github.com/civicrm/civicrm-dev-docs/pull/189

Content in it needs to be re-oragnized into multiple other pages. We'll
leave that for another time.

In second paragraph remove space between "overview] (https" to read "overview](https:" so that URL does not appear adjacent to "basic overview".

* They have been moved to the CiviRules Guide:
  https://docs.civicrm.org/civirules/en/latest/
* Close #183

Identify two environments:  Docker for Windows / Mac / Linux and Legacy
OS (Windows 7, 8.1, 10 Home Premium).  Provide docker run commeands for
each environment.

Close #184

Close #86

This way the docker image shows the repository that was used to generate
the image and people can go to that repo to look at the Dockerfile used.

This updates the docs to ensure that hook parameters exactly match the names
in the code.

Prior to 4.7.19, the names of hook-parameters didn't really matter (as long
as they were in the right order).  In 4.7.19, the names took on extra
significance because Symfony-based listeners use objects and fields (e.g.
`$event->firstParam`) instead of ordered params (`function($firstParam)`).

 * Rewrite "Events"
 * Use more consistent style in the two examples
 * Move some "notes" into new section, "Methods"

What's wrong with a little inversion of logic?

Updated line 627 to "For use with CiviCRM 4.3 and later," per info from @totten

Add links to other documentation, clean up grammar and formatting, clarify a couple points