This replaces --connection-count, for more customization, but without requiring
more configuration from the user.

The previous broadcast model is replaced by a query-response one.
During normal operation, the cache of peers is not used anymore to select
peers to connect to. It now only used for bootstrapping and avoid querying
an already known address.

Co-written with Ulysse

using the same socket for sending and listenning

A peer now advertise itself more at the begining to be as present in the local db of other peers than the average

Currently, a peer broadcast its address to evrybody but this should change

Conflicts:
	re6st/tunnel.py

Re6stnet now create a socket and listen on it. The socket is not used yet

solve a bug in an SQL request

tunnel manager now display checking tunnels instead of refreshing tunnels when it only replace the dead ones

    When the bootpeer was blacklisted, it was still inserted in the peers table
    When 0 tunnels had to be made, re6stnet asked for 0 unsed peers, recieved an empty list and thought he had to ask new peers to the server