User manual: Update sections 4 and 5

A new figure is included to reflect the actions of the new profile buttons
on the calculated ceilings.

A number of small edits on sections 4 and 5 of the user manual are done.
These sections are now finalised for the new release.

Signed-off-by: Willem Ferguson <willemferguson@zoology.up.ac.za>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>