* Further streaming lib caching improvements
* Reduce the minimum RTT (used to calculate retry timeouts), but also
increase the RTT on resends.
* Lower the default message size to 4KB from 16KB to further reduce the
chance of failed fragmentation.
* Extend tunnel rebuild throttling to include fallback rebuilds
* If there are less than 20 routers known, don't drop the last 20 (to help
avoid dropping all peers under catastrophic failures)
* New stats for end to end messages - "client.leaseSetFoundLocally",
"client.leaseSetFoundRemoteTime", and "client.leaseSetFailedRemoteTime"
238389fc7f