BUCK: performance configuration
BUCK: performance configuration

 - parallel parsing BUCK file
 - spooling Java class files directly into jar without storing
   them on disc

Change-Id: Icfb724fc00a83494aa42b404d23742799cfb41d0

BruceZu/KeepTry,BruceZu/KeepTry,BruceZu/KeepTry,BruceZu/sawdust,BruceZu/sawdust,BruceZu/sawdust,BruceZu/KeepTry,BruceZu/sawdust