Merge pull request #725 from KevWright/master

Fixed two links
Merge pull request #726 from KevWright/master

Various fixes and consolidation
Merge pull request #727 from KevWright/master

Fixed a link
Merge pull request #728 from KevWright/master

Fixed formatting issue
Merge pull request #729 from KevWright/master

Fixes for examples section
Merge pull request #730 from KevWright/master

Fix for overview section
Change title of section to make identical link inside work.
Tie the edit_xml bundle docs to the edit_xml files attribute.
Merge getting started into guide main page.
Rename markdown file.

Original filename had incorrect spelling and was anyway different
from the title.
Comment out empty statement in known issues.
Remove obsolete page.
Editing introduction and components documentation.
Fix sorting of sections within the Guide.

Also, unpublish the upgrade guide as it's not relevant for 3.6.0.
Fix links to learning center.

Use new predefined reference.
Move documentation of cf_promises_validated out of introduction.

Not sure that the configuration file structure is the best place, but
it's definitely better.
Ordering of pages under introduction, and some light editing.
Sort and tighten up the installation guide.
Move the syntax specification into the language concept documentation.

Understanding when to quote what is fundamental knowledge and not
part of the reference.

Ditto for filenames.
Fix a bunch of links.

Note that it's possible to use implicit linking if the link text
is identical to the title of the page you want to link to.