* Subclass from Clock a RouterClock which can access router transports,
with the goal of developing it to second-guess NTP results
* Make transports report clock skew in seconds
* Adjust renderStatusHTML() methods accordingly
* Show average for NTCP clock skews too
* Give transports a getClockSkews() method to report clock skews
* Give transport manager a getClockSkews() method to aggregate results
* Give comm system facade a getMedianPeerClockSkew() method which RouterClock calls
(to observe results, add "net.i2p.router.transport.CommSystemFacadeImpl=WARN" to
logging)
* Extra explicitness in NTCP classes to denote unit of time.
* Fix some places in NTCPConnection where milliseconds and seconds were confused
9325b806e4