ovs-bugtool: Log more detail for dumped flows.

The standard mode for printing flows doesn't always provide the full
range of information that is available, particularly with the UFID
changes. Turn on more detail.

Suggested-by: Justin Pettit <jpettit@nicira.com>
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Gurucharan Shetty <gshetty@nicira.com>