CONTENT (E.G. LOST+FOUND) IN DATADIR

Reused the --ignore-db-dir list for the files in the database
directory being created by --initialize.
Now --initialize considers the data directory empty if all
it has is entries starting with "." or  entries that match
inside --ignore-db-dir list.

Had to move the initialization of the list before the datadir
creation to support that.

Added a test case.