Change DB schema to handle IPv6, remove primary keys as some clients will reuse download_id
Change DB schema to handle IPv6, remove primary keys as some clients will reuse download_id

Signed-off-by: Michael Casadevall <9d4f4ab526b9cf89b20618261f2c6e1070ae1dbe@ubuntu.com>

eustasy/phoenix,eustasy/phoenix,eustasy/phoenix