change package name and sbt project name to rocket

rocket/src/main/scala/dpath_util.scala

@@ -1,5 +1,4 @@
-package Top
-{
+package rocket
 
 import Chisel._;
 import Node._;
@@ -269,5 +268,3 @@ class rocketDpathRegfile extends Component
   io.r0.data := Mux((io.r0.addr === UFix(0, 5)) || !io.r0.en, Bits(0, 64), regfile(io.r0.addr));
   io.r1.data := Mux((io.r1.addr === UFix(0, 5)) || !io.r1.en, Bits(0, 64), regfile(io.r1.addr));
 }
-
-}