DB schema converted from 1.9 to 2.0

Much better now.

Still: indexes changed are not re-created. To do a better work a
procedure drop_index_if_exists() should be create to complement
create_index_if_not_exists().
Then changing an index will follow this path:
1) create a new index with a different name
2) add a call to drop_index_if_exists() to dbconfig.xml, with the old
name

CCBUGS: 276356