modulares Backup-script für Unix-rechner
- if logfile is empty, it will be deleted
changed the way of handling symlink creation
reduced file to backup only system-relevant files
- separated configuration to backup.conf-file
 - only base parameters migrated
improved error-handling
- improved separate config-file (reading, detection)
- improved error-handing (fails when subscript fails)
implemented some simple way to backup ...
- changed way of generating default for tasks-directory
- renamed "tasks"-directory to "tasks.d"
- removed debug-output from "tasks.d/01-system"
- corrected variable "HOLD_BACKUPS" to "BACKUP_KEEP"
added test for valid setting to "tasks.d"
- added $BACKUPFILE_PREFIX (to name files according to date)
- modified scripts to observe $BACKUPFILE_PREFIX
- postgres: changed parameter -D
added ${BACKUPFILE_PREFIX}
1st working version to backup MYSQL-database
 - script inspired by postgres-script
FEATURE: making "work-tasks" optional
 - all tasks are avail in "tasks.d-available" 
 - relevant tasks for system shall be activated by linking to "tasks.d"
belongs to r464: example for individual task-activation
changing LDAP-backup
 - current way of just archivign the Database-files is renamed to "ldap_filecopy"
 - implement alternative way using "slapcat" (task: ldap_slapcat)
IMPROVE: using the debian-default locations
 - working in two steps during archiving, to avoid archiving only 
   the symlink of the "archives"-directory (tar -h)
 - error-handling in case the archive was not created
ADD: a hackish way to implement the "LVM-snapsot"-feature to
 create backups of data that may be written to during backuping
 - in this special case it's used to store the maildirs of IMAP
IMPROVE: also backup the "mysql.events" table
 - also get rid of the warning that this table will not be backuped