Fix for "missing" block stats and issue #362

Sometimes block stats were not printed because P2P managed to switch to sync mode and sync block flow control was not printing reports. Now it does, but only if its block is close to current time. Also broken blocks should no longer look like valid in block stats. Since fix for issue #362 (closed) was similar to those changes, it was also applied (pending transactions are just rewritten without being applied when related block was not close to current time).

Needs schemas!27 (merged)