Do not use the \returns command as it does not exist.
Do not use the \arg or \param commands (use \a instead).
Do not use the \see command (use \sa instead).
Remove \brief command from function descriptions for
consistency (as it is optional).
Fix punctuation, grammar, and style issues.

Change-Id: I11173b84146cccf7fe9ba29a521cea93e03a4424
Reviewed-by: Thomas Hartmann <Thomas.Hartmann@digia.com>