* Change rate check logic to avoid DoS attacks
* Convert rate check to use object timestamp instead of arrival time
* Update cached variables before checking for superblocks
* Ensure that last times are monotonically non-decreasing
* Bump governance manager serialization format
* Improved rate check error reporting
* Increase quorum for object deletion to 2/3 of MN network
* Implement expiration of watchdog objects
* Remove objects from the watchdog map itself
* Message fix for invalid objects
