manual: Re-order chapters in more logical order

It makes a lot of sense to first describe the VTY interface before
going on using it to configure something.  Also, configuration related
topics relevant to operators/sysadmins should precede other content
only relevant to developers, like the details of the CTRL or Abis/IP
protocol.

Change-Id: I0872d072bbb06f9409a72b93133d136167f03b38
1 file changed