GitLab

Adds D2 developer's guide

Fixed the main page table of contents to include D2's sections as subpages
Minor word changes and clean up

Added src/bin/d2/images to image path in doc/Doxyfile
Added d2 subpage to doc/devel/mainpage.dox
Added the following:

Also, updated configure.ac to not reference removed files. The
--disable-dhcp and --disable-dns configuration flags have been removed.

Thsi is another test of git with new repo

This is mostly just a test of using new git repo for kea.

fixed many typos
also consistently spell and capitalize PostgreSQL.

as reported on dhcp jabber

(discussed a little on jabber)

(maybe this should be automatically set to current year)

(blame it on my broken laptop which randomly types simulated "x"
characters which is delete char in vi. I should have the diff reviewed!)

One change was not in any released version and then was reverted.
So remove it.
So change the revert message entry and renumber some entries.
This was discussed via jabber a couple weeks ago,
but nobody reviewed my patch for this.

grammar
PostgreSQL like project shows the term
typo fix
mention DHCP