blockpool stability fixes:

- follow up locks and fix them
- chainManager: call SetQueued for parentErr future blocks, uncomment TD checks, unskip test
- make ErrIncorrectTD non-fatal to be forgiving to genuine mistaken nodes (temp) but demote them to guard against stuck best peers.
- add purging to bounded nodeCache (config nodeCacheSize)
- use nodeCache when creating blockpool entries and let non-best peers add blocks (performance boost)
- minor error in addError
- reduce idleBestPeerTimeout to 1 minute
- correct status counts and unskip status passing status test
- glogified logging

logger/glog/README

@@ -19,20 +19,20 @@ The comment from glog.go introduces the ideas:
 	Error, Fatal, plus formatting variants such as Infof. It
 	also provides V-style logging controlled by the -v and
 	-vmodule=file=2 flags.
-	
+
 	Basic examples:
-	
+
 		glog.Info("Prepare to repel boarders")
-	
+
 		glog.Fatalf("Initialization failed: %s", err)
-	
+
 	See the documentation for the V function for an explanation
 	of these examples:
-	
+
 		if glog.V(2) {
 			glog.Info("Starting transaction...")
 		}
-	
+
 		glog.V(2).Infoln("Processed", nItems, "elements")