Fixing the perf subproject that broker after the sbt upgrade

perf/build.sbt

@@ -0,0 +1 @@
+name := "kafka-perf"

project/Build.scala

@@ -87,7 +87,7 @@ object KafkaBuild extends Build {
     "bin/run-rat.sh" !
   }
 
-  lazy val kafka    = Project(id = "Kafka", base = file(".")).aggregate(core, examples, contrib).settings((commonSettings ++ runRatTask): _*)
+  lazy val kafka    = Project(id = "Kafka", base = file(".")).aggregate(core, examples, contrib, perf).settings((commonSettings ++ runRatTask): _*)
   lazy val core     = Project(id = "core", base = file("core")).settings(commonSettings: _*).settings(coreSettings: _*)
   lazy val examples = Project(id = "java-examples", base = file("examples")).settings(commonSettings :_*) dependsOn (core)
   lazy val perf     = Project(id = "perf", base = file("perf")).settings((Seq(name := "kafka-perf") ++ commonSettings):_*) dependsOn (core)