debian/copyright: update the debian copyright file

Fix up the debian/copyright file so it contains the full information
of the licenses used by all of the libraries.  Also use a single
copyright file for e2fsprogs and e2fslibs, to make sure they are kept
in sync.

Addresses-Debian-Bug: #614662

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
4 files changed