user - a name of the user with which rights all daemons
	of David system works;
 
default_email_recipient - the default e-mail address
	where messages from David system applications are sent;
 
bindir - the directory containing David system applications
	(default: /usr/bin/david-system);
 
libdir - the directory containing David system libraries
	(default: /usr/lib/david-system);
 
incdir - the directory containing David system headers
	(default: /usr/include/david);
 
confdir - the directory containing David system configuration files
	(default: /etc/david-system);
 
logdir - the directory containing log files of David system applications
	(default: /var/log/david-system);
 
sharedir - the directory containing various files
	(images, audio files, web files) of David system (default: /usr/share/david-system);
 
docdir - the directory containing various files
	(images, audio files, web files) of David system (default: /usr/share/david-system);
 
vardir - the directory containing archive files
	of David system SQL database (default: /var/lib/david-system);
 
is_sqldb_installed - the flag that indicate whether
	the SQL database of David system has been installed or not.