move to MULTI_PACKAGEs (the no_bat PSEUDO_FLAVOR is still available).
This modifies the packages as:
bacula-client - no change
bacula-server - the server part, now unflavored and depends on a proper SQL package support
bacula-bat - no change
bacula-mysql - new, MySQL support for bacula-server
bacula-pgsql - new, PostgreSQL support for bacula-server
bacula-sqlite3 - new, SQLite3 support for bacula-server
All SQL support packages conflict with each others.
For users of mysql and sqlite3, a manual step will be needed to properly
upgrade bacula-server; sthen@ will take care of this in current.html.
Tested by myself and sthen@
ok sthen@