Co-Authored-By: Mikey O'Toole <mikey@mjco.uk>

Added to line 22 - "You shouldn't run the curl buildkit command as sudo. It will sudo itself for the bits that need it."

removed a reference to an Issue with installation on Mac OS, which is now Closed - https://github.com/michaelmcandrew/civicrm-buildkit-docker/issues/15

Actually I think we should put the 'other platforms' first & the more specific options at the end though

Add health warning about running Docker on OSX

Added documentation on Michael McAndrews docker container.

Tim and I added these instructions to amp (and improved them) so now
it's better to remove them here.

Just spotted a typo in my previous change.  That 'v' should have been an 'h'.

The command `which civibuild` returns nothing even if the path is set correctly.

As noted earlier in the doc: "We strongly recommend using Apache as your
webserver because support for nginx is limited." So...  it doesn't make much
sense to give broken/incomplete instructions for something we say you
shouldn't do.  :)

Add in help message about troubleshooting where you cannot login to buildkit build because rewrite mod isn't enabled

Clarify Nodejs instruction line.

Reading for content; editing for consistency.

Edit to paragraph format rather than short lines.

Make the warning about running Ubuntu installation as root slightly more dire.

- General formatting improvements.
- Change  "Ubuntu 12.04 or 14.04" to "Ubuntu 12.04 or later" because the
  buildkit install script is clearly designed to work for later versions
  of Ubuntu.
- Relocate troubleshoot steps to after configuration steps (so the
  reader doesn't stop reading when they see "troubleshooting".
- Higlight post-installation steps.
- New instructions for manually ading webserver settings after running
  `amp config`.
- More troubleshooting help.

This was in the general "buildkit" page, and I think it fits better in
the specific "civibuild" page.

This is a direct copy-paste from one section of the guide to another,
without any edits. When someone is installing buildkit, these steps are
easy to miss if they're located in the civibuild file.