script «update-bacula»

Changes:
2011/12/08 - added a new optional configuration parameter: RESTORE DIRECTORY;
2011/01/26 - automatically create the storage directory if not found;
2011/01/25 - DOMAIN is not hardcoded in the script, made optional;
           - parameters can be adjusted from /etc/default/update-bacula;
           - white spaces are not allowed in path names (cache directory);
           - display a more useful and clear status update to console;
2010/08/13 - changed the default restore directory for all restore jobs
             from "/tmp/brestore" to "/var/tmp/brestore" which allows
             the sysadmin to create a persistent symlink (across host
             reboots) to a local directory that has enough free space;
2010/06/01 - removed "Max Run Time = 2 hours" as buggy (see bug #584135);
           - added full path to the procmail "lock" file exclusion;
           - added full path to bootstrap files (backup and restore);
2010/05/27 - added support for maximum volume jobs (MAXVOLJOBS);
           - changed compression to GZIP instead of GZIP9 for backups to
             complete faster (also there is a little difference in size);
           - switched to SHA1 signature from MD5 as it is more secure;
           - added an 'exclude' directive for maildir-* backups (lock files);
           - bootstrap files are associated one-to-one to volume names;
           - "Priority" is 10 by default in the Job definitions;
           - corrected "Bootstrap" directive for restore type jobs;
           - added "Max Run Time = 2 hours" to the jobs definition;
           - added CLIENT:SCHEDULE in the summary since one client may have
             multiple jobs but scheduled at different execution times;
2010/04/21 - added support for volume use duration (VUSEDURATION);
           - fixed a bug which override all previous records for CLIENT;