bgp: local preference support

add local preference support in bgp. It is possible to apply local
preference to specific paths by using AttributeMap.

Unfortunately this patch supports only IPv4 path and I'm going to
start writing patches for other route families after this.

Signed-off-by: Hiroshi Yokoi <yokoi.hiroshi@po.ntts.co.jp>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
of: Fix Enum Name for Bad Instruction Code Corrected Reset Count enum name

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
of: Fix Enum Names and Values

Fix Enum Names and Values in OpenFlow Header files Update no matching
name in packet-in reason as specified in OpenFlow 1.4 Update queeu
stats name in in multipart type as specified in OpenFlow 1.4 Add
additional constants as defined in OpenFlow 1.4

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
of: Add missing fields in OpenFlow statistics messages

update statistics structure to reflect OpenFlow specification.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Add OVSDB manager application
Switch to IDL
Patch Vlog to use std logging
Split out client from manager
Dispatch events for schema modifications
Don't expose Row objects
add some logging
Add todos
Moar logging
Adjust spacing
Start on modifications
move fsm initialization into start()
Use ryu Apps for every connection
Add transaction support