First add, then create replies to similarity_request
DiscoveryCommunity wasn't attached when it resolved the trackers, fixed
Add random when replying
Merge pull request #296 from NielsZeilemaker/discoveryv1.3

First add, then create replies to similarity_request
remove walk_advice* statistics
remove walk_bootstrap* statistics
change some statistics to properties
remove WalkStatistics
fix rebase bug
change for optimize mode
simplify endpoint statistics
some cleanup
some fix for tribler
fix rebase problems
some fix
use dispersy.send_packets() instead of endpoint.send()
some fix
change some strings
put walk statistics into dispersy._send()
put walk statistics into community.on_message()