remove installation section in quickstart and link to install page

[michelleN]

[itowlson]

I'd prefer not to do this. Asking readers to exit the quickstart, perform a task (which now has extra options because the install page tries to be comprehensive), and then navigate back to the quickstart (instead of following the "next steps" on the install page) seems like it has too many points where readers can wander off. I'd much prefer to keep the quickstart a straight top to bottom with all the info you need for the happy path.