Add the appendix marker `\appendix{}`

Add the command `\appendix{}` between the sections listing figures and
tables, and the include command for the bibliography.

The purpose of the `\appendix{}` command is to flag the end of normal
chapter numbering, and the start of numbering for the appendix. Adding
this command now means that layout between branches should remain
consistent.
Format 'ChangeLog' to follow GNU's standards

Modify the contents of 'ChangeLog' such that its contents is organised
in the way described in the [GNU coding standards][1].

Following a standards document allows more time to be spent generating
content than worrying about how it is presented.

As an aside, a small note now exists at the top of the document
detailing what exactly can be found in the file, and how its contents is
arrange.

   [1]: http://www.gnu.org/prep/standards/html_node/Style-of-Change-Logs.html