Allow flushing source-specific updates.
Allow specific updates to be bufferised.
Add some guarded code to handle requests in a near future.
Fix useless fields in interface.h.
Improve route printing with "from" field.
Add local interface source-specific printing.

It also update the route's id.
Add options to control the table and priority numbers.
Add filter to match source addresses.

Add 3 new options to configuration and manpages:
src-ip, src-eq, src-le and src-ge.
Set the source prefixes through filters.

Since it's a route attribute, it fits better there.
Pass NULL instead of zeroes.

We pass NULL here because prefix is NULL.
Format TLV for (standard) requests.
Format TLV for unicast requests.
Format TLV for multihop requests.
Format TLV for unicast multihop requests.
Make send_request_resend deal with source prefixes.
Make handle_request deal with source prefixes.
Parse source-specific request.
Move parsing of message_request_src_specific.
Parse source-specific multihop request.
Move parsing of message_mh_request_src_specific.